Why it happens is because you cannot find a genuinely creative person with the drive and motivation needed to keep pushing a juggernaut like Blizard forward who

Why it happens is because you cannot find a genuinely creative person with the drive and motivation needed to keep pushing a juggernaut like Blizard forward who would be willing to drop their own creative vision and adopt the one of the original founders. Who knows what they'll do? When its time to eat plates of shit will they do it? It's far too much risk to put an unknown in that position. Your only option is to send in the corporate fleet because they're predictable. Even if they've failed before they will never surprise or throw out any curve balls to investors and shareholders and that's valued far above the possibility of a new creative spark achieving something.