That's such a gross simplification that it's highly misleading. Yes you need training to if your work involves ladders, just like any other tool that is potentially dangerous. The type of training highly depends on the danger, so for someone using a stepladder to get something from a shelf will not need more than "use the ladder from the closet, put it back after use", while someone climbing up to the antennas on a skyscraper will receive very different training (i.e. always clip in your safety harness, how to use double carabiners ...). I don't know how this is controversial?