Steve Krause : Blog

A Tale of Two On/Off Switches

On the left is a baby monitor by Summer. On the right is a speaker by Logitech.

The baby monitor's on/off switch is integrated with the volume dial. You click on the unit at zero volume, then dial up for higher volume. Thus, every time you turn on the unit, you need to reset the volume. For extra frustration, the dial has no indicator for the volume level.

With a baby monitor, finding the right volume is a delicate balance. You want the volume high enough to hear your child call or otherwise make significant noise. But you don't want so much volume that you're hearing ambient noise in the child's room. It would be so much better to set the right volume once and leave it there.

Enter the Logitech speaker (part of the X-230 three-piece set), which gets this issue right. The power switch and volume knob are separate. When you turn on the unit, the volume is where you left it. This design probably costs slightly more than having a single knob/switch, but it is unremarkably right—that is, so natural you don't notice it.

Errant Error Explanations

You are on an airline's Web site, one where you've registered before. You want to log in, and it asks you for your email address. You enter the email address, but the site says, "Invalid email address."

You look at the email address. It's correct.

You try again. "Invalid email address."

At a recent conference I attended, a speaker told this story from the airline's point of view. The engineer responsible wrote the code to look up the email address provided. Anything other than a match returned "Invalid email address" because, from the engineer's perspective, that's what it was.

However, a significant number of people were entering valid email addresses, just not the ones they registered with. Many people got stuck there, thinking the site was somehow telling them they didn't know their own email addresses.

Having discovered the problem, the airline did two things:

• Changed the error message to something like, "We don't recognize that email address. Did you type it correctly, or could you have registered with a different email address?"
• Reviewed all other error messages on the site with customer-facing professionals.

The lesson: What happens when things go wrong needs as much consideration as what happens when things go right.

Airport Usability: Where Is My Baggage?

Arriving on a flight to Chicago O'Hare International Airport, I saw this:

A few notables about the sign:

• It's obvious. The sign is the first thing you see out of the jetway. It is impossible to miss.
• It's concise. The sign tells you where your baggage will be. It does not waste your time by telling you where other flights' baggage will be.

Surely this is better than the normal routine of wandering around the baggage area searching for clues.

Highway Exit Numbers: When Simple was Too Simple

In design, simpler is often better. But some solutions are too simple. The history of highway exit numbers in the United States provides an example.

Highway exit numbers are numbers that accompany names of highway exits. They appear on many highways (especially interstate highways) in the United States. Here is an example from Interstate 4 in Volusia County, Florida.

[The image is from Wikipedia's "Exit number" article, as are other examples below except where noted.]

Originally, exit numbers were sequential. So if a highway had 200 exits, they would be numbered 1 to 200. From the motorist's point of view, it could not have been simpler.

But when a sequentially numbered highway needed a new exit, the scheme's simplicity went from asset to liability. For example, if a new exit was being added between exits 20 and 21, would the former exit 21 become 22? And would the former 22 become 23? And so on. Given the cost in dollars and confusion, renumbering all the exits from a new exit forward was not an option.

What to do? "Hmmmm, a new exit between 20 and 21....Let's call it 21A!" And so it was, until another exit was needed between 21 and 21A. On the New York State Thruway, the solution was to go with the sequence 21, 21B, 21A, 22. (If you are asking yourself whether you read that correctly, you did.)

This kind of situation led to the rise of distance-based numbering, where the exit numbers are the same as the highway's mile markers. Example: Exit 21 would be 21 miles from the highway's numbering origin. (In the U.S., highways going north-south have their numbering origin at the south end; highways going east-west start numbering at the west end.)

Of course, the distance-based system handles the problem of new exits much more cleanly than the sequential scheme. The distance-based system reserves numbers corresponding to the miles where there are no exits. Since most new exits are necessary to fill gaps where there are no exits, a new exit will usually have an unused number waiting for it.

But what if a new exit is within the same mile marker as an existing exit? From the Wikipedia article:

If two exits would end up with the same number, the numbers are sometimes modified slightly; this is often impossible and exits are given sequential or directional suffixes, just as with sequential numbers.

So in a worst-case scenario, exits that are too close together get sequential numbers or letters tacked-on to their distance-based numbers. This is still far better than the original sequential-numbering scheme, because the ugliness involved with changing sequential numbers is contained to a few exits at a time.

That said, the distance-based system does have an Achilles' Heel: If a highway's origin were to change, all the mile and exit-number signs would need to change. Although this situation would be as bad or worse than a renumbering caused by a new exit in a sequential-numbering system, it is far less likely. That's because, out of all the places a new exit can be, it needs to be at the beginning of the highway to disrupt the distance-based system. In contrast, a new exit any place other than the end of the highway would disrupt the sequential system.

In summary, distance-based numbering is not a perfect solution, but it's a better one. Sequential numbering's simplicity assumed no change to the system being numbered. When that assumption was violated, sequential numbering proved too simple to adapt. As a result, most U.S. states now use distance-based numbering for interstate highways.

Let It Roll, Baby, Roll

It is said that the ancient Central American Olmec culture invented the wheel for children's toys but never made the jump to using it for transporting things. By today's standards, such an important oversight seems difficult to imagine, but our modern society has its own versions of this story.

If you are a frequent traveler, you almost certainly have luggage with wheels. Compared to carrying your luggage, rolling it is a big advance. When did this advance occur?

From eBags' Bagopedia:

Although the wheel dates back to pre-history, modern rolling luggage did not appear on the scene until around 1989. The story goes that Northwest airline pilot Bob Plath was tired of lugging his heavy overnight bag and flight bag through airports around the world. Being a creative kind of guy, Plath spent weekends working on a wheeled "pilot" bag in his garage. The new wheeled bag was an immediate success. Whenever and wherever Plath's wheeled luggage rolled on the scene, everyone wanted one. Bob Plath's company TravelPro was born and the rest is history. Before too long, TravelPro held 15 patents on a diverse line of rolling luggage. Other luggage companies quickly caught on and went wheeled.

"Alright," you say, "our age of innovation didn't notice this one obvious application of the wheel for a while, but surely it is an anomaly."

No. I can testify to the next example, because our family is apparently an early adopter of the wheeled car seat: It's like rollable luggage, except the "luggage" is your car seat, which attaches to a roller frame, like so:

The picture is the gogo Kidz Travelmate from GogoBabyz. I don't know who the child is.

The scenario where a wheeled car seat applies is this: You are flying somewhere with a small child, and you will be driving at your destination. Normally, you would carry a car seat as a piece of luggage (or as carry-on if your child will be sitting in it on the plane). When added to the multitude of things you need to carry in support of a small child, a bulky car seat is not a welcome addition.

By adding the roller wheels to your car seat, you not only get the roller effect on the car seat, you can also roll your child in the seat. We have rolled our daughter through numerous airports, and similar to the story above about people stopping the roller bag inventor wherever he went, people always ask where we got it or comment on how clever an idea it is.

So, even today, a technology as fundamental as the wheel is still spinning-out new uses.

E Ink: A Tale of Two Applications

Last week, in explaining why I was underwhelmed by the Sony Reader, I mentioned E Ink. It's a display technology that uses tiny microcapsules that can be controlled like pixels. Once the microcapsules are arrayed into an image, they require no further power; they continue to display using reflective light.

Although E Ink—at least in its current state of development—was not compelling to me in the Sony Reader, I'd like to offer a compare-and-contrast with a simple yet compelling E Ink application: Lexar's JumpDrive Mercury, a pocket USB flash drive with a percent-full gauge.

Exploiting E Ink's "powerless display" advantage over other electronic displays, the gauge is readable whether the JumpDrive Mercury is plugged in or not. When you think about it, the only time the display can change (and thus need power) is when the drive is plugged in (and thus has power). Nice.

Also, the JumpDrive Mercury leverages another E Ink advantage over traditional displays: the ability to be packaged very thin and light. For pocket USB flash drives, small is beautiful, and the E Ink display in the JumpDrive Mercury adds precious little mass or volume to the device.

Finally, as important as exploiting E Ink's advantages, the JumpDrive Mercury's use of E Ink is not penalized by E Ink's disadvantages against other display technologies. Lack of color and a slow screen refresh are not a big deal for a gauge on a USB flash drive. In contrast, they are problems for the Sony Reader, which is potentially competing with colorful, instant-refreshing LCD devices that can do a lot more (like multimedia) on top of e-book reading.

So, although the JumpDrive Mercury does less with E Ink than the Sony Reader, what it does it does well.

In Praise of the Apple Corer

One of my favorite examples of good design is the apple corer. As a simple, efficient solution to a problem, it has few peers in the kitchen.

This apple corer slices an apple into eight sections while separating out the core. Just put it over the top of an apple and push down.

But wait, you say, isn't a knife an even simpler tool: a single blade and a handle? Indeed a knife is a simpler and more versatile tool. But for sectioning an apple, it's an inferior solution.

For a knife to achieve similar results to the apple corer, you'll be making several slices into a wobbly apple. If you're reasonably fast and accurate, you might get it done in 15 seconds and still have your fingers intact. Meanwhile, I will have been done in roughly 1 second, without concern for slicing flesh instead of apple.

So if you are a regular apple eater, it's worth using the right tool for the job. When you do, savor the difference.

Sign Usability: San Francisco Does the Right Thing

Last month, I noticed this road-sign usability issue (4th Street, between Folsom and Harrison in San Francisco):

The sign, which was about three feet behind the pole, points the way toward the local baseball park, AT&T Park, the name of which has changed an average of once every two years since its opening in 2000.

A week later, I saw that the City of San Francisco had moved decisively to improve the sign situation...

...not only making the sign visible but also following the wisdom of the previous sign, which restricted itself to the generic term "Ballpark."

Hearing Glasses

Here is an inspired idea: "hearing glasses," an eyeglass frame that also function as a hearing aid.

The problem being solved? Because they amplify all sound coming into the ear, traditional hearing aids are often useless in noisy environments. For example, I have a relative who avoids restaurants because she can't hear what people at her table are saying amid the amplified background noise.

Hearing glasses start with the assumption that a person is most interested in sounds that she is facing. To distinguish sounds in front of a person, hearing glasses have an array of eight mini-microphones, four along each arm of the glasses frame. By using the tiny differences in time between when a sound reaches each microphone, hearing glasses' integrated processor can calculate where the sound is coming from. (The human brain locates sound in a similar way, comparing when a sound reaches each ear.)

With sounds located, hearing glasses can amplify front-facing sounds—like the person talking to you—and diminish (without eliminating) rear-facing sounds. The glasses even have a charging station for when they are not being worn.

Hearing glasses have just been released in the Netherlands, where they were developed by the Delft University of Technology and Dutch company Varibel.

It's such an elegant and useful idea that I really hope the product delivers on the promise.

[Originally seen at News.com, "Improve your hearing with a new pair of glasses"]

Windows XP and Tivo: Don't Confirm When You Can Undo

For most Windows XP users, attempting to delete a file gets you this: "Are you sure you want to send '[file name]' to the Recycle Bin?" Despite its familiarity, this confirmation feature has long been scorned by many user interface designers. We can understand why by looking at a better approach from Tivo, which recently eliminated its confirmation for deletes. Then I'll explain how you can get Windows XP to do the same thing.

Tivo: Doing Delete Right
Before Tivo's March 2006 software update, if you pressed delete while you had a show selected, Tivo asked whether you really wanted to delete that show. Now Tivo doesn't ask; the show just goes away. However, the show goes to an area similar to Windows' Recycle Bin, where the show resides for a while before permanently disappearing. Thus, if you make a mistake, you can recover the show.

So what's the benefit? Assuming you usually mean to delete a show when you select "delete," it just works. Yes, you may make a mistake 1% of the time, but you can undo it. Meanwhile, for the other 99% of the time, Tivo does not require you to confirm that you are not making a mistake. Thank you, Tivo.

Windows XP: How to Delete Like Tivo
With its Recycle Bin and its "Undo" menu selection, Windows XP already has a way to undo mistaken deletes. The bad news is that Window XP nevertheless retains the "Are you sure..." confirmation for deletes. The lesser-known good news is that you can configure Windows XP to suppress the confirmation: Right-click the Recycle Bin icon, select "Properties," uncheck "Display delete confirmation dialog," and click "OK." Deleted items will still go to the Recycle Bin but without the confirmation.

If you change that Windows XP setting, deleting files will feel righter, similar to Tivo's new way of handling deletes.

Synthetic Pets and the Power of Precedent

My colleague Scott Danish made an interesting point about the power of precedents in how people evaluate something new. We were talking about Pleo, a robotic toy introduced at DEMO 2006. Pleo is a cute dinosaur that's supposed to be like a pet, capable of interacting with you and expressing emotions. It's best seen rather than explained:

    Video of Pleo
   
So why a dinosaur? Scott pointed out that, unlike a more familiar choice for a pet like a dog or cat, dinosaurs have more favorable precedents for consumer acceptance. First, we often think of dinosaurs as relatively slow-moving, stiff creatures. That's a lot easier to represent robotically than, say, a dog, which Sony attempted with its now-canceled Aibo.

Perhaps more important, nobody has a real pet dinosaur. This lack of a tangible precedent gives people more room to project whatever they want onto little Pleo. And that matters because a key to any synthetic pet's success so far—whether stuffed animal, tamagotchi, or robot—is the user's imagination.

Bottom line: Put Pleo in an dog- or cat-like casing and its success as a toy gets more difficult. That's the power of precedents.

(For a good write-up about Pleo in terms of Ugobe's business strategy, see Rafe Needleman's write-up.)

Hefty OneZip: A Usability Puzzle

Hefty OneZip bags are plastic zip-lock-style freezer bags. When you take one out of the container, you'll find it closed.

As the default state for a product, it's hard to picture something more backward. If you are going to use the bag, you need to open it. Why not just provide the bag already open?

A few possible answers:

- Manufacturing the bags already opened might cost more than manufacturing them closed.

- Consumers might perceive a closed bag as more sanitary. However, the bags come flattened and wrapped within a sealed cardboard box, which would seem to minimize the contamination threat.

- The product designers might not have considered the issue, randomly ending up with closed bags.

Whatever the reason, it's not a big deal, just a small usability puzzle.

Update, 8/1/2007: The third comment below, by "Anon," provides what seems like a highly credible answer to this puzzle. In short: (1) manufacturing in the closed position enables a tighter seal, and (2) the FDA requires it for sanitary reasons.

Microwave Oven Usability

In the time around Ava's birth, I was in and around the hospital a lot. Different wards have their own galley kitchens, each with a communal microwave oven. In using the microwave I was puzzled to see that it almost always had a small amount of time remaining from the previous person, who apparently stopped before the countdown was complete.

The hospital microwave was meant to be used as follows: Push the "Power" button, then select a power level, then push the "Time" button (which does nothing if you push it before pushing the "Power" button), then key-in a cooking time, then push the "Start" button.

It's a relatively standard sequence for microwave ovens, but if you don't know it, the front panel gives no hints. However, there is an "Add 30 Sec" button, which I found myself using as a shortcut, pushing multiple times until it showed the time I needed. In my case, the time I needed was divisible by 30 seconds, so I used the full countdown. But at some point I realized that most people probably did the same thing with the "Add 30 Sec" button, except they pushed "Stop" when their time (which was not divisible by 30) had counted down.

The lesson: A microwave with 16 buttons was getting used as if it had two buttons, including by me who knew how to use it the intended way.

Meanwhile, at home we have a relatively new microwave oven, a GE SpaceMaker 2.0. It attempts to be more user-friendly, with a touchscreen interface and multiscreen menus, including various forms of help. Here is the top-level screen:

It also has shortcuts for cooking or reheating food types like "popcorn" and "fish." While fine for popcorn, the feature usually disappoints due to the variance in cooking required for different types of "fish," "rice," "fresh vegetables," and such.

Still, I applaud GE for trying; it's a step forward. But now that we've got a touchscreen instead of fixed buttons, can't we be simpler? For example, why not let me push "Start" from a list of the last four settings I've used? Something like this:

Task	Power	Time
Cook	10	1:45	[Start]
Cook	10	4:00	[Start]
Reheat	5	0:45	[Start]
Cook	10	2:30	[Start]

Because we tend to use the microwave for a few things frequently, and for everything else rarely, this feature could be highly effective—at least for home use, not necessarily for communal use. Another way of doing it would be like speed dial on phones, where a setting could be recalled by pressing 1, 2, etc. (The SpaceMaker 2.0 has user-configurable "custom" buttons, but they don't have the same level of intuitiveness that a "recent list" or "speed dial" feature would have.)

The point: At the hospital, people faced with 16 buttons improvised their way to the goal by using only two. In that spirit, the touchscreen's promise is to offer not just more choices but the right choices, in context. The fact that, even with the SpaceMaker 2.0, I still often use the "30 Sec Express" button mutiple times—and, in terms of minimizing button pushes, it is rational to do so—means more improvements are waiting to be made.