Most of my non-bike riding friends are middle-aged or elderly (don't know how that happened - they were young when I met them). They are uncomfortable and intimidated by bikes with 24 or 27 speeds and a position that puts their nose down by the front tire.
Last year I gave a NBRF a single speed Trek beach cruiser. Coaster brake. Big, wide seat. Handlebars up high. Ultra easy gearing that make pedaling up a hill easy. She now enjoys relaxed rides around the neighborhood. So, next, I'm giving her a three speed which also is easy to ride - maybe someday she will want to ride a mega-complex bike - but if she sticks with simple bikes - so what?