The sad truth is that a lot of the western teams, but mostly the top NA teams think they're a lot better than they actually are. So they think signing up talent from solo queue is beneath them.. Since it's the in thing to buy a few Korean players and hope that magically fixes all the issues your team has, many incredible challenger players get ignored. Even signing them up into the B team and giving them a chance to prove how good they are would be nice to see.