I am the author of the post. You raise a valid point.
Just having your friends work there shouldn't be the only reason, but them working there and being happy is a good proxy for the work and the company.
Re: friends leaving, if you review the research in the post, it suggests that like refer like, i.e. your best performers will recommend others at a similar level. It's also symbiotic in that the presence of friends makes them stay longer.
Of course nothing is guaranteed. This approach just reduces the odds of disappointment on both sides.
Shailesh
To me, the job interview is a mutual interview, i.e., I am interviewing the employer while they interview me. And when it comes to deciding on teams/projects, I use the probationary period as if it were an extra due diligence after the interview to decide if the work is interesting (much as the employer gets the time to decide if I really am a good fit and productive).
I think many people have been sold by founders and interviewers on the greatness of a set of projects only to find the scope or robustness of those projects to be much less.
Thanks for the post.
(Notice the emphasis on solely; obviously having your friends working at a company is a plus, but should not be your complete basis for working somewhere)
You are a lot more motivated to give it your all when you know a friend or family member is relying on you then some random strangers you happen to work with.
You can't have a united, motivated team that you can chop up however you like without consequences.
A recommendation from a friend will outweigh any bullshit a founder will spew at you.
Actually selling at that point is counter productive since if you are trying to sell too hard he will get suspicious.
Being friends with an existing team member was more predictive of choice than project interest, and for many of the reasons the OP's article cited (job satisfaction and trust)