There is an interesting thread in the LA board and I realize many people in the SF area may not visit the LA board so I thought I would start one here as well.
For reference: http://www.theeroticreview.com/discussion_boards/viewmsg.asp?MessageID=309941&boardID=1&page=1#309941 Personally, my only bad experience was with the first girl I saw, big mistake thinking lower priced escorts would be as good as the higher priced ladies. Since that one time, paying the extra, every session has been very good, and every time I have done a second or more sessions with a particular girl it has only gotten better. So, the question, do you feel sessions get better worse or stay the same with multiple visits as they did the first time?It really depends on the provider. Some built a connection with you and learn your preferences, while others get comfortable and don't try as hard.
I've had good experiences with repeat sessions for the most part.
The more you get to know someone, even if it is only a bit, the better the rapport and the better the experience. However, the key is the first meeting and whether a sense of connection is present. Often times there is none, which is no ones fault, just a fact.
Things never stay the same for me. If there are multiple visits, then things get better and better. If it's the same thing, why go back. It could be a number of different things, but something extraordinary has to happen to get me to come back a second time. It has to happen again for a third visit. The magic number for me has always been four. If things keep getting better by the fourth visit, there will be many more visits, extenuating circumstances excluded. There are many many ladies I've seen twice, or even three times, but for one reason or another, we don't get around to that next session. Maybe because things stayed the same, or they got worse. Of course, this being what it is, even the long term relationships are doomed, eventually. Even so, those are really nice memories. This is going to sound weird, but when you've seen someone so many times, in your mind, it's almost like they're an ex girlfriend when you both move on.
mojojo,
Are you sure its not just because you like variety to much. 
I'm of the mind that it doesn't have to get better than the first if the first was outstanding, as long as it is not worse I'll gladly go back over and over.
The last point is very true. All of these connections will end. Just hope that it leaves you (both) with good memories.
Extraordinary isn't so hard.
You're right though - eventually, almost everything does end.. And when you lose a genuine connection with a genuine person, it's not easy... for either party. It's good to be able to reminice and only have amazing memories, though. 
I can't say the same for actual boyfriends I've had!
You're right. Extraordinary isn't hard. Once or twice. But three times in a row seems to be hard. That's why things don't usually go beyond that third session for me. But find a lady or two who can make extraordinary happen fifty times in a row, and you've got something special. The memories are wonderful, but you keep thinking, what the hell is she going to do on that fifty first session?
Your boyfriend line is so funny AG. You must have had some doozies. One would almost think we should date provider/clients. But you have to remember, providers and clients are usually on their very best behavior. Not so, the real life bf/gf. Too bad! Still, the great times are amazing, either place.
It is really about how it ends. A bad ending can ruin the experiences that were otherwise extraordinary...calling the entire time shared into question. It leaves you with the sense that the whole thing was fake or contrived or some sort of scam. Disappointing...but it happens, and makes it harder (but even more important) to move on.
The better you get to know someone, the more you know just what to do, and when to do it.
However, sometimes in the process of getting to know each other you find out something you were not expecting, and the relationship must end. Sad when that happens.