I have once---a regular provider referred me to one of her friends who wanted to try things out.  She was awkward as a hostess (in general); the apartment was not ready for prime time, and the friend was awkward in all the ways one could be awkward.  i reported back to my regular ' I don't think she is made out for this', and my friend said 'I kind of thought so too'. Continued happily with my regular...

I had an appointment at an AMP. I got there expecting to see Soi but found out that mamasan had lied to me about Soi being there that day. She told me to wait and, after a few minutes, brought in New Girl, "Brand new girl! First day!"  

New Girl was still in civvies, unusual for your typical AMP, and already teary-eyed and upset. I was sitting on the bed (still clothed) and mamasan pushed her over to sit down next to me. I tried to assure New Girl using sign language and pidgin English that this was NOT going to happen. I made it much more clear to mamasan that it wasn't going to happen, too. I then excused myself and left

I have twice. Once, she told me, and the agency confirmed, that I was her first P4P client and she ROCKED! She's gone on to be a real rockstar in P4P and I can't afford her $500/hr rate.  
The second one was more recent and I suspect I was her first because she really had no idea what she was doing - it was pretty bad and to make matters worse, one of my favorites recommend her.  Not everyone can be an escort, a good one anyway. Lots of girls see the money that their escort friend makes and decide they want to try it. It's easy! Right?Unfortunately, I think I just had one of those encounters with a new escort trying to learn on the job.

My first "client" knew he was my first because I was working for an agency and the owner of that agency always got his new girls to see one of a handful of select clients who would reback to him how the date went. Agent had already told the client I hadn't worked as an escort before.

Having  said that, I'd already been in porn a number of years.. so It wasn't like I didnt know what to do!

Over the years in managing houses in OZ, I've had to train girls who were new.. if they were a bit nervous or inexperienced I'd join them in an a double with a regular house client for their first appointment.

Not sure it was her first day on the job but she was very new.  

Not a disaster but different.

I ended up seeing her about 8 more x. LOL

and yes, it got better and better

I saw a girl as her first P4P with an agency I was a regular customer with.  The booker told me, I always trusted his recommendations so went for it.  She was very young, maybe 19 or 20, but very comfortable talking about sex, which was refreshing and helpful.   Great kisser,  she loved daty and came so many times she finally put up hand laughing and said "stop, please".  Repaid me with awesome bjcim.  She said she'd swallow if a guy asked, and she went on to be a long-time star at that agency, known for her bbbjnqns skills.  I saw her a few more times, and she was always great at everything, but I could tell she was a natural at sex that first time.