This kind of experience happens with some regularity. Clearly, for whatever reason, the girls keep working well-past the enthusiasm mark, and those last sessions are going to suck.
Assuming it’s voluntary, then the girls are just squeezing a few extra Benjamins out of a day, and the houses have no real motivation to curb them, as there’s always a line of horny mongers waiting, especially for the popular girls.
But we get doubly shafted, both with a lousy but expensive session, and with the guilt of fucking a non-responsive body.
I wish there was a way to prevent this, but I can’t see how, other than arriving early in the girl’s schedule.