Because when you’re young and healthy, usually the time when most people start smoking, the risk of having lung cancer or other tobacco related diseases seems like a far too distant and improbable threat. It’s the kind of thing that only happens to others, old people, people with bad genes, people with a history of cancer in their family.
By the time most people realize the danger, smoking isn’t just a pastime anymore. It’s a habit similar to having lunch, dinner, a drink, it’s part of your personal and/or social life just like eating and drinking. In fact, after several years most people have had more cigarettes than meals or drinks, it’s something to consider.