Michal, I don't mean to offend in any way, I just wanted to post this because I think the incident was funny (because the girl got what she deserved) and it fits to the topic:
2. Make sure you have skills, knowledge and equipment
My wife used to be engaged in offroading when she was younger. She had an old model Toyota Land Cruiser with Super Swampers (the car still exists and is in traffic actually, but with (more) normal tires).
There was another girl offroader, a cocky girl with a Jeep. When the group of off-roaders were talking about off-road cars in general, the girl announced that "I don't have an off-road car, I have a Jeep". Shortly afterwards, she got stuck.
Maybe that was because she didn't have an off-road car ;)