Most important things when choosing a hostel?

Hello World! I’ve have sometimes found myself booking hostels instead of hotels when I travel. I like the vibe, but I don’t like the lack of privacy. However, when I talk to other people when traveling, sometimes people say that they don’t care about the lack of privacy (private rooms) – it just doesn’t matter to them. Also it seems like some people only chooses hostels where there are parties and events - which I personally don't care about.

This made me wonder: What are your 3-5 most important things you look for when choosing a hostel? (except the price)