I think a lot of people, not knowing if they will like cycling, get a cheap bike from a mass retailer and find they don't like cycling. I didn't care too much for riding a crap bike either. When I got old enough, my dad explained to me where my enjoyment of cycling was going wrong, and that it was probably time I got a better bicycle. That made all the difference. Many folks don't have that sort of guidance and examples in their family, and a lot of others find that their spouse has issues with them riding when they should be spending every waking moment at home, etc. I've always been lucky enough to have people supportive of cycling around me, but i can easily see how others have it. I now also live in a town quite committed to cycling, where I grew up, and the period in which I grew up, not so much. Even now not great, but far improved.