docschleg
Friendship Hours, Official
You need to invest 50 hours in someone before they become a "casual friend", and 200 hours before they can become a "close friend". It's science, so deal with it. Check out an article about the article here:
https://www.cnn.com/2018/04/23/health/acquaintance-friend-partner/index.html
Here's the abstract of the original article:
http://journals.sagepub.com/doi/abs/10.1177/0265407518761225?journalCode=spra&