Have you cum? No It's not physically possible for a woman to climax with every client. Unless she has that spontaneous orgasm dysfunctional thing. You know the one where they sneeze & climax.
What would you like? I'd like a guy to come in, pay me, rub my feet then piss off.
I had one who'd booked for 30 mins, the other week, ask me if I would squirt. I replied, not unless you book for 2 hours & know your way around female anatomy. He was 25.
As for the clueless finger thrusters, I just push them away & say "I'm here to pleasure you". Or if I'm in a really bad mood I'll prod the end of their cock or similar & ask them if they are enjoying it.