I guess that for those couple of border cases, it's true that there wasn't a "good reason" why they were denied. But for the majority of applicants, there is a

I guess that for those couple of border cases, it's true that there wasn't a "good reason" why they were denied. But for the majority of applicants, there is a good reason - because YC didn't think that you were one of the 50 or so best startups. This doesn't mean that being denied means that you're not smart or dedicated or that your startup is bad. It just means that they didn't think it was one of the 50 best they received.