https://techcrunch.com/2022/04/27/how-to-get-into-y-combinator-dalton-caldwell/

Y Combinator’s batches are getting bigger and bigger. Its first batch back in 2005 was made up of just a handful of companies — this latest batch came in at over 400. But that’s out of over 17,000 that applied!

What gets one team in where another is turned away? If anyone can answer that, it’s Dalton Caldwell, managing director and group partner for YC. He’s been with YC for its last 19 batches, with much of that time spent overseeing admissions. He puts his tally for the number of applications he’s reviewed in the “tens of thousands.”