Gmail is good. I like Gmail. But I fuck up and archive an email by mistake at least once a day, because for whatever reason, some loaded diaper in Mountain View decided to use the same icon, twice, for EXACTLY OPPOSITE FUNCTIONS.
Here's Gmail's Archive button:
And here's the smaller but virtually identical icon for "Expand All" in a thread:
No, I don't actually care that the Archive button is on a box with a white line at the top, while the Expand all has a white line at the bottom, representing... something. It's an arrow on a square. It's the same damn icon.
Can you make the argument that given years of use, I should have learned to stop fucking this up by now, and furthermore, that as interface components, both are situated in the correct positions—Archive as a prominent button in the top-centerish, Expand All nested in the upper right with a more targeted set of functions—and that the iconography remains logical for both actions, while also consistent with the overall language of the design? No. Fuck you.
You archive an email when you're done with it and don't need to think about it anymore, and you expand a thread when you need to think about its contents immediately. They are literally, perfectly opposing ideas and THIS IS THE SAME FUCKING ICON C'MON. You can see how this is a problem, since, in general, good UX isn't building websites the way Dr. Doom builds space stations. Is this the door to the bathroom or the one that will suck me out into the cold vacuum of space to die? I don't know! They look exactly the same!
(To actually acknowledge the position that this is a real debate wanting for real rationale for action—which, to be clear, I don't at all, but this doesn't even make sense if you do—I expand a whole thread far more often than I archive something, which I think is normal behavior, and having Archive all big and clickable and Expand tiny in the corner is a crap layout.)
This is never getting fixed. I don't actually care all that much that it's never getting fixed, aside from the fact that I've been buried in email for the past week and have accidentally archived every other fucking thread. Google has cleaned up a lot of its design over the last few years, but there's still plenty of residual flotsam like this left unswept.