I hate when magically appearing scrollbars cause the screen to redraw - I especially hate it when the content needs a scrollbar if NOT present, so it appears, which makes the content reflow so it doesn't need it, and it keeps swapping back and forth.

Good times.

There has been a bug in Apple's Quicklook on macOS for as long as I can remember, where the right side of a document is slightly cropped when Always Show Scrollbars is enabled. It appears to expect that the scroll bars should only appear intermittently and renders over the content.

Very frustrating when one is scanning documents and photos, and verifying them through Finder shows phantom cropping.

I personally like the scroll bars to always be visible as they serve as both an indicator and a control.

It's really annoying that you need to click on something that the scrollbar covers up or steals focus from.