I think it's ingrained in a lot of people as kids. You have a bike to go around to your mates quicker and go for a kick around at the local park. Maybe even ride to school. Beyond that, you learn to drive and then cycling is forgotten for most owing to the world opening up and you can go anywhere in reasonable time, dry, warm, with a stereo and with the luggage space.
As a kid, riding a bike was the quickest, easiest, and cheapest means of covering shortish distances door to door - say five miles or less. I've been on two wheels since I was about four, and although I've ridden a lot less since I learned to drive and got into cars, I've always still owned bikes and there has never been a time when I've been without one. For an 18 year old with a reasonable job and money to spend, bikes don't have quite the same appeal as they do to a 14 year old. Cars were better for having liasons with girls away from parental prying eyes for a start. A drive somewhere in a warm dry car beats a cold wet bike ride any day of the week.
Unfortunately, one side effect of the ease of covering distance in cars is that people tend to then move further away from friends & family and live further away from work. Then the original easy convenience of a car becomes an essential, because riding to work is often simply not practical and all your social circle tend to gradually spread further apart because they also move further away from friends and work and the whole thing self-perpetuates. Unfortunately, given the trend for many employers to rationalise operations and concentrate their activities into fewer sites that might entail longer trips to work, I really don't see cycling making that much of a comeback in terms of the percentage of total journey miles cycled. At the margins, the odd extra journey might be made by bike rather than car or public transport, but I don't expect any wholesale change. To achieve that both business and public services would have to reverse all the things they've been gradually doing in the name of "efficiency" for at least 30 years - shops post offices, bank branches, council & government offices, would all have to be decentralised and placed closer to where the public actually reside. Technology will never fully do away with the need for face to face interaction, and how locally you can interact has a big influence on how much travel is done by what means.
