You have a highly mobile and mercenary workforce, many alternate employment opportunities with similar benefits (e.g. none), a clearly defined goal (food, on time), high frequency of repetition and a short time to failure loop (great for learning or improving), a reputation with fickle customers to maintain, and a broader taste zeitgeist one has to chase.

It's a hard as nails job, but I learned a lot about management.

Also: un- or semi-documented immigrants usually work twice as hard as Americans, for terrible wages, and are the engine of almost every kitchen. So special note and tons of respect to all the people out there sweating to prepare food & improve their and/or their children's lives.