My biggest pet peeve in interface design is the popup that says “Are you sure that you want to leave this page?” when I navigate away from a web page. I see this as mostly being used by sketchy advertisers. I chose to navigate away from the page; it isn’t up to you to question me.
Note to reputable web sites: Don’t ask this question. Just let me do what I have chosen to do.
My second biggest pet peeve are questions or UI elements that are designed to trick you into making a choice that you did not want to make. Apparently these have a name – Dark Patterns:
A dark pattern is a user interface carefully crafted to trick users into doing things they might not otherwise do, such as buying insurance with their purchase or signing up for recurring bills. Normally when you think of “bad design,” you think of the creator as being sloppy or lazy — but without ill intent. Dark patterns, on the other hand, are not mistakes. They’re carefully crafted with a solid understanding of human psychology, and they do not have the user’s interests in mind.
The article provides several excellent examples, but I am always reminded of the olden days when I used Windows and products like Norton and other bloatware would ask questions at install time in such an obtuse way as to get you to install them when you really didn’t want to.
If you are a reputable company with a good product, just ask the user a straightforward question. Otherwise it just seems like you’re trying to hide something.