A 19 year old freshman at the University of Oregon received a hard lesson in the importance of basic bicycle maintenance recently. According to news reports, the young man was riding his bicycle to class when his front tire fell off causing him to flip over the handlebars and crash, landing on his face.
While it may seem that this kind of an accident would be an isolated or at least rare occurrence, it happens more frequently than you may think. Particularly if you have quick release hubs on your wheels. Do yourself a favor. Inspect your bike regularly and check your wheels before every ride.