There are few things that universally qualify as web design FAILs. The esteemed Jakob Nielsen has a list of Top-10 Web Design Mistakes from 1999 which, in web years, is a long time. Long enough that you think people would have learned.

Arguably, most of the ten mistakes he lists are not so hard and dry. For instance, it is not too hard to imagine situations in which opening a new browser window (mistake #2) is not a clear cut screw-up. And some of the mistakes are less serious than the others, e.g. #8, “jumping at the latest internet buzzword.”

But there is one holiest of holies that you just don’t mess with: breaking the “back” button. The back button is the second most used browser action, right after clicking a link to follow it. Breaking the back button is a clear signal that you haven’t thought, or don’t care, about your users.

So why does Fido.ca’s Phones & Accessories store think they’re above this? It’s aesthetically pleasing, but trying to compare phones on their website was easily the most frustrating web browsing experience I’ve had in a long time. While I usually think it’s not very helpful or informative to be so flippant, in this case I call: user experience FAIL.