Lately, I’ve struck upon a new benchmark for usability: the extent to which the interface disappears. Let me explain —
My wife drives a Honda Odyssey minivan. This is the Swiss Army Knife of minivans. It’s set-up perfectly, to the point where I’ve often said, “If you need to find something, close your eyes and use your gut instinct to reach out to where you think it is...and it’s probably right there.” The “interface” of that van disappears. It’s so usable, you don’t even think about it.
I’ve discovered this with two apps with which I’ve been working a lot lately:
GMail GMail takes a lot of liberties with how email works, but I don’t even think about the changes. I just expect that a “conversation” will have a list of emails in chronological order. I just expect that a new email should be considered the “reactivating of a conversation.” It just works.
The silverorange Intranet This is an old favorite of Gadgetopia, and it’s something we’ve been doing some super-secret work with lately. In the course of this work, I had a long running intranet-based conversation with one of the principals at silverorange. It was during this conversation that I realized that the tool had vanished from my perception, and all that was left in its place was pure communication. There was a point where the tool become such a natural part of how I worked that it just faded into the background.
I remember reading a tutorial a while back about dynamically adding form fields to an HTML form (this was a few years ago – back when this was a really novel thing). The author said that when you do this, your users shouldn’t even notice. Being able to add an extra phone number field dynamically will feel so natural to them, that it won’t even jump out as being a technological achievement.
This, in my mind, has become the true measure of usability, and it’s a combination of a lot of things: interface architecture, visual design, application performance, browser interaction, etc. In a perverse way, the highest compliment someone can pay your app is that they never even noticed it was there.