Comment by scarface74

Banks have methods to try to limit churning some are explicit like Amex “once per lifetime rule” where you can only get a sign up bonus for a particular card once.

And they have what is colloquially known as “pop up jail” where when you try to sign up for a new card, they will allow you but pop up a warning saying you won’t get the bonus if you apply for the card. It’s based on your previous behavior with them.

But even while the algorithm for how they choose it is secret, it’s been reverse engineered for the most part via crowd sourcing.

Most credit cards also will deny you if you have opened too many recent cards no matter what your credit is. For instance I just got denied the CapitalOne SavorOne card that had 10% cash back for Uber and I have an 800+ Fico.