Some clients I can’t tell either way if they care if I cum. There have been plenty of times - primarily as a bottom - when I haven’t cum at all. Not because I wasn’t enjoying myself, just because they didn't seem interested in me cumming. Didn’t feel like that’s what it was about. Though you’re making me wonder how many of those guys were disappointed!
I do have regulars who are clearly very invested in my orgasm and I always cum for them.
Have you made it clear that it’s important to you?