Customers suck, that's why.

Seriously, she thought you were scolding her for having a bike in such a state of disrepair, I guess.

I should say, though, that I am far from expert on this subject since I was possibly the worst bike shop employee in the world for my rather limited time in that field. I hated selling, so I avoided the counter and customers. I hid in the workshop doing repairs and builds. Also, I would cheerfully ignore the limited repairs outlined on the ticket and spend godawful amounts of time doing general cleaning and tune-up of customers bikes. Really. That's the sort of behavior that should have given a manager/owner an ulcer. I just loved to make things (even crappy things) work better.