Quoting Yuri Fassio
I wonder why the Empire stopped using them...
That is because the Empire never used them, that would have been the Confederates, and last time I checked, Anakin had to go and kill those guys. Plus, the Emperor had extreme prejudice towards aliens and robots, using them only as an end to a means. That and 3rd rate writing! LOL Wow, I always wanted to sound like a Star Wars nurd. Oh yeah, great Droideka!~H