I've lived in a lot of places, and I've never once had to take any kind of exam to renew a license. Not sure who told them you need to do that - I don't think that's a thing in any US state, and probably not in most countries either.

Renewal of a license is mostly just updating the photo.

You can also transfer licenses between states with no exam. Not necessarily between countries though, some allow it some don't.

I think the OP was talking about an initial license though - for the most part exams are not very hard, you just need a basic level of skill, and some knowledge.