Re: Why????????
I can tell you it is from a pure lack of knowledge, for the most part. Up until 4 or so years ago, all I ever knew about motors is what I got from watching my father (a desiel mechanic mind you). He would pull the motor out of the basement in spring and put it on the boat, head out to the lake and fire it up. He would run it out of gas each time (don't want a carb full of gas in the basement). I don't remember him doing any maintenance at all, other then running the tank just about out at the end of the year and filling it back up the next spring, with maybe one lower unit change. He may have done some work on it when I was not around, but nothing that I knew about. He passed when I was 20 and my mom gave me the boat and motor. Eventually I killed the motor due to lack of knowledge of two strokes (ran it too lean and damaged the something inside).
I am sure many people get motors second hand (either buying them or handed down) and see them the same as cars, you run them, possibly do basic stuff like plugs and lower unit oil, and take them to the shop when something does not seem right. To most I am sure that a boat motor is just a bigger version of a lawn mower or snow blower, and think how people treat those. Just about everyone I know that has a boat has never done a water pump impellor, some will do lower unit oil, and even less will winterize. With the knowledge I have gained over the last few years and seeing what people do, I am surprised that half the motors on the water still run.