I don’t imagine that, in medicine, a neurosurgeon who was being considered for a life-saving operation finds out that the patient chose another surgeon because . . . the patient’s wife and the other surgeon’s wife are best friends.
But that kind of thing happens to Realtors all the time.
People understandably want to do business with people they already know and trust.
It’s also the case that not going with the Realtor cum son-in-law/best friend/cousin would risk jeopardizing important relationships.*
However, it’s hard not to conclude that at least some of the foregoing preferences reflect ignorance about how the real estate business works — and specifically, an assumption that “all Realtors (and Brokers) are created equal.”
Interview a few, and you’ll likely find out otherwise . . .
*Of course, it’s also the case that some people assiduously avoid working with friends and relatives, because of the threat(s) it can pose to the relationship.