There are lots of situations where it's best to take a break and leave things be for a while. It's different for everybody, and you want to be careful not to do it too much.

I can think of many times where I've started working on an idea or part of a song and got nowhere, only to try it again days or weeks later and discover that it was much easier.

Of course I was playing in the meantime, I was just focusing on other things.