It might help if y'all would separate all those different issues/questions you're mashing together.
1.
Discretion. Yes, a
call at a time he hasn't said is OK can be indiscreet. But email or PM or other methods of contact are less significant.
2.
Hard sell/direct solicitation of another appointment. Yes, that can be annoying to some (not all) customers, whether you're talking P4P or selling books or whatever. But that reaction by customers may not -- probably does not -- extend to other forms of contact. Such as . . .
3.
Soft sell/polite follow-up. Such as an email or PM a day or two later thanking him for coming to see you, and even expressing in general terms (without getting as specific as "Hey, wanna come see me this afternoon?") a sentiment like "I really enjoyed our time together and hope you come back some time." Depending on the circumstances, e.g., if he's seen her a few times, even an occasional (not frequent, and not if he doesn't respond the first time or two) email or PM to "Hey, I was thinking about you and wanted to say hi; hope everything is going well!"
The original poster may just have talking about something along the lines of #3. I suspect very, very few P4P clients would object to receiving such a follow up. In fact, most would receive it as a very positive indication that their business is valued. They might still go back to see a lady who didn't, unlike the original poster . . . but, if everything else were equal, follow-up along the lines of #3 would probably make most clients more likely to come back. Lack of follow-up won't make me think she doesn't want to see me again. But if she does follow-up, it may make me feel more like a valued client; if I were considering seeing her again anyway, I might be more likely to do it sooner rather than later.
Outside of P4P, that type of follow-up is not all that rare. Most businesses prefer repeat clientele and are always looking for ways to encourage that without being too intrusive. "Thank you" notes or the like are one way that is often done, and very rarely if ever offend the recipients. Yet, in the world of P4P, some ladies forego #3 because they're told that #1 and #2 will irritate the client.
Customer relations. An important (but sometimes neglected) aspect of
any job that involves marketing or selling.
That, I suspect, is what the original poster was saying. There certainly is no requirement that the ladies do that, and it may not matter to most of your clients. But with some, it may.
------------
Edited to add: From another thread:
Frankly, I'm not likely to become a repeat customer unless I'm solicited...too many other fish in the sea tugging on the line for me to arrange dates with everyone I'd like to see.
Originally Posted by TinMan