Developer is too general a term for deducing an ideal mindset.

A tester should be empowered by defeating the system. That's also great for some kinds of development (like in security). For some systems, it's better to be empowered by seeing the things you build grow as you act, for others, it's better to be empowered by seeing they grow by themselves after you act. There are places best fit by people empowered by ensuring no problem arises (also the dominant mindshare in ops), by comprehending things none could before, and by making hard things easy. There are probably places for other people that I'm overlooking too.

Testing is a much more standardized position.