"It isn't perfect, but it at least gives those who don't come from money --which is by and large, most people-- a chance at a decent life." What are the chance

"It isn't perfect, but it at least gives those who don't come from money --which is by and large, most people-- a chance at a decent life." What are the chances at a decent life anyways? Is the chance a good one? What is the worth of a meritocracy if you do all the right things and stull only get a probability of a right life?