Oh gaps are usually pretty interesting. I once dug into a big gap (3 years) and went down quite a rabbit-hole with a candidate that was in every other respect excellent.
But the gap: Let's just say it was the worst thing you can imagine.
3 year gap would stick out for sure. I think it's also depends heavily on when the gap was, and what followed after.
Now I'm intrigued but I'm assuming something like jail/prison. :D
Nah, that's just the first thing you've imagined.
I think: commander of concentration camp for disabled ponies and baby elephants.
The worst thing I can imagine would hardly leave only a 3 year gap.
Prison for almost killing their interviewer for asking about an employment gap.