Why do we feel the need to play matchmaker?

I don't think that my older brother needs to date my friend Rachel. I'm not sure he's into someone so much more athletic than himself. And yet, after she moved to San Francisco, I gave her my brother's number and told her he'd probably be willing to take her flying if she ever wanted to try taking airplane controls. Rob has a pilot's license and goes up whenever he has the time and wants to spend the money on gas. I'm sure he'd be nice to Rachel as she is friends with myself and my younger brother. I actually know that my older brother hates set ups, so when I notified him that I'd given out his number to a friend, I mentioned that I didn't think they'd make a great match but she is a fun person to hang out with.