Used to get a lot of strange guys going pro that had no chance of getting drafted before NIL.
I feel like a lot of kids surround themselves with the wrong type of people and they get blatantly incorrect advice on when to go pro(see Kofi). In Black's case he had a medical redshirt but had been in college for 4 years so it's possible he graduated and just wanted to try to play professionally(which he did do in South America), but yeah he probably would have been better off sticking around and picking up a graduate degree or certificate in a 5th year and then going pro.
Jeremy Richmond is the all time most baffling one imo. Never any shot he was getting drafted after his freshman year and he actually might have had a chance to get drafted after his sophomore year if he kept his head on straight and improved. Nearly 8 pts and 5 rebounds in 20 minutes as a freshman isn't terrible production to build off of and McCamey, Davis, and Tisdale were all out of eligibility.
He could have probably become the go to guy on a starting lineup that could have actually been pretty good running out Richardson(jr.), Paul(jr), Bertrand (so), Richmond(so), and Leonard(so).