A dear dear friend is my groomer. I had my first yorkie when I was in college (1980's). At that time, I wasn't too keen on brushing and pampering every day (actually, nobody was really - times have changed.) So, Rex always had some really bad mats!
Anyway, I'd bring my Rex to my friend to groom about every 6 weeks. I'd always be excited when it was time to pick him up. I'd be thinking that my baby was sooo good, sooo wonderful, sooo sweet - and that he'd never be a problem for my friend, the groomer.
Well, even before my friend would bring Rex out, she'd come up to the front counter and say, "Tracey, you know what?? Your dog's a #&@*!-head!" Then she'd hand me my Rex with a beautiful Lion shaped head and shaved body.
Moral of the Story: It's not ALWAYS the groomer's fault. Some pups do not behave on the table and get the best that can be done.
BTW: My friend is a top, experienced, well-known & loved groomer - so I can't blame her. It was me, all me.