Some of it requires training. Sometimes, people will come up with things on their own based on certain observations. As a matter of fact, I recently did so myself. About two weeks ago, I was at the gas station filling up. I normally lock the grip so that it can pump hands free. That particular day, I was standing behind the hose as it was pumping.
As the gas was pumping, I noticed a few guys in front of the store getting loud and belligerent.
What if something happened, and I needed jump in the car and speed off? In that situation, I would have to remove the hose or step over it. And either the the gas will keep pumping after I'm gone (costing me serious money and causing a major fire hazzard), or spend the valuable one or two seconds that could make the difference, and click off the handle and put it back. Or, I could walk around the car to avoid the hose, but this would give up the cover that the vehicle provides. And probably take longer than removing or stepping over the hose.
Luckily, nothing happened.
But from then on, I will never pump gas hands-free again. And I will always stand in
front of the hose, so that I have clear and obstacle-free access to the door to get in.