Rare insults

This is also true. I think the app owners want you to get a steady trickle of so-so but imperfect matches. If you get nothing, you'll leave. But if you keep almost getting it, you'll come back. And maybe pay for that "premium" service. It's a trash business model.

Match-makers where you pay once has a better incentive, since the longer you're in the system the more labor they have to do, but those tend to be expensive.

OKCupid had a blog post about why you should never pay for dating services, but after they got bought by Match Group that vanished.