"We also think these breakouts aren’t necessarily a good way to judge accelerators." Is Y Combinator a bit arrogant to say that the success of its startups is

"We also think these breakouts aren’t necessarily a good way to judge accelerators." Is Y Combinator a bit arrogant to say that the success of its startups is a bad a metric for evaluating their success? If it is a bad metric, what's a good metric?