SM being the #1 undisputed label in SK for at least a decade led to trainees flocking to SM for a chance to debut. SM truly believes that if you debut with them, even if your group is just mildly successful you'll still be better off than 90% of idols in small companies. They use that justification to treat their idols and shit and make slave contracts. I mean think about it, would flop pelvis still be a known group if they had debuted with anyone other than SM? 
Of course when you look at the reality of the situation it all falls apart, but SM truly justifies their immense power as a company to treat their idols like shit.
