“GAW: The only service a shadcahn can provide to the singles is getting them quality dates (and helping with the technical, advising were asked and approprite).”
I don’t compensate my plumber, electrician, etc. for effort, (to use your example) only results.
If the plumber asks for payment (before starting) even if the problem is not solved, they may not be hired.
As I have said before, I have no problem if this compensation scheme is stated before the shaddchan starts. I do have an issue with this becoming the norm.