When they said Reddit has 2000 employees I was shocked. what could they possibly do onto a website that is basically run by users (and sysadmins) and that is basically feature-wise mature? I really can’t figure out 2000 people working every day on Reddit… on what? just for a quick comparison, the whole IAmA was run by a single person (Victoria), so… what are they doing?
I believe another part of it is that companies that get venture capital money are also encouraged to hire more employees, because VC’s care about growth.
If you are a company relying on the support of venture capital and you aren’t hiring people to grow the fastest, then the VC might decide to just fund your competitor instead.