Zappa is notorious amongst drummers for his brutal auditions. He wrote parts for the applicants to play, parts intentionally extremely difficult to play. Some found him to be a sadist who enjoyed humiliating other musicians. One drummer Zappa was very impressed by and greatly respected was Vinnie Colaiuta.
But different writers/musicians value different playing "philosophies"/styles in their accompanists/sidemen. Danny Gatton, a virtuoso guitarists-guitarist (a far better guitarist than Zappa. Ask anyone ;-) had very different tastes in drummers than did Zappa.
Gatton to his new drummer during the break after the drummer’s first set on stage with Danny:
"You know all that fancy sh*t you play?"
The drummer: "Yeah."
Gatton: "Don’t."