Hacker News Reader

I don't think they intended to grow slowly. When they launched, there were similar aggregators already (digg?). I think they just kept the site under the radar long enough to become sort of a Craigslist for content. The design was antiquated and simple, userbase was limited but loyal. It just caught on from there, sometime around 2012-2014 when people wanted more content per unit of time invested (vs other social networks).

reddit grew fast and was acquired just over a year after it launched (which was in June 2005): https://techcrunch.com/2006/10/31/breaking-news-conde-nastwi...

I'm fairly sure YC's stake in it was bought out at that point.

YC's stake maybe, but Sam Altman followed on as a lead investor later: https://www.reddit.com/r/IAmA/comments/2hwr02/i_am_sam_altma...

Look at how early Reddit was in YC’s history. QED.