The turnover, as elsewhere in the fast-food industry, is horrendous. Coworkers are great, but the managers are overbearing, micromanaging, unprofessional, and often extremely condescending – to the point that they drove most of the talented individuals away. I've been asked to work on my break (which, even in the context of "hey could you hand me that," is still illegal and abusive).
Crew members are expected to memorize and recite handouts of essential employee characteristics, as well as customer service fundamentals, which I found rather degrading. These stores want cogs; not intelligent, thoughtful people. If you are one of the latter, you will burn out.