Hidden interface controls that affect usability

Only tangentially related, and a seemingly lost old-man battle: stop hiding my scrollbar.

Interesting article. Some points I didn't quite agree entirely with. There's a cost and practically limitation to some things (like a physical knob in a car for zooming in and out on a map - although that was probably just an example of intuitive use).

I just recently switched a toggle on a newly installed app that did the opposite of what it was labelled - I thought the label represented the current state, but it represented the state it would switch to if toggled. It became obvious once changed, but that seems the least helpful execution.

I recently used the washroom at a Starbucks. The one where you have to enter a code to get in. Once I was inside, there were no knobs or any mechanical way to lock the door - just one circular button with a lock icon on it. I pressed it, and the button lit up as green. Pressed it again, it lit up as red. No indication on what light colour meant what. Does red mean it's unlocked? Or does it mean it is locked, since red usually indicates no entry.

It made for the quickest pee break ever.