A few days ago, my wife decided to order some business card-sized prints from Moo. After we uploaded the photos and typed in the text, we realized that several of the photos were cropped wrong. So, we clicked the button at the top of the screen for “Step 1” or “Step 2” — whatever one corresponded to editing the photos. Sure enough, the system let us change the photos, but when we returned to the text editing step, all the text was gone. Bummer.

Apparently, Moo doesn’t save your work unless you complete the steps in the exact order they specify. To be clear, we didn’t hit the Back button or do something else that normally trips up web apps. We just clicked on the step number. The link worked normally, without any warning. And that’s the whole problem: we never got an error message saying that going back a step would delete all our text.

In a perfect world, your application would let customers navigate back and forth while automatically saving their work along the way. But when that’s not possible, you need to tell them if the action they’ve requested is going to erase their work or have some other nasty side effect. That way, they can decide if the benefit of making those changes is worth the cost.