Why did people invent four wheelers?

Four wheeled ATV's were the next logical step from the 3-wheeled ATC (All Terrain Cycle). Opponents of off-roading almost put a stop to the introduction of the 4 wheeler. Look at any current production quad and count the number of warning stickers/labels. This was a concession manufacturers had to make in order to allow the sale of 4 wheelers at all. Even with that, the sale and use - and the safety record - were under heavy scrutiny. Much more maligned than even the snowmobile, it seems you either love them (ATV's), or you don't.

The mode of transportation is now entrenched and has bread it's own spin-offs. Quads area very popular in rural areas.