I have no doubt that experience is the best teacher. I’ve taken many a lesson to heart after I’ve made boneheaded mistakes. For example I have tied into an anchor with a girth hitch instead of a clove hitch. That was a mistake that I took to heart and ended up writing this post. Another prime example is when I forgot my goggles during a winter ascent of Mt Washington that featured 100 mph gusts of wind loaded with spindrift. My glacier glasses were worthless in those conditions and I was basically climbing blind. Or there was the time that Ben and I got delayed at Laurel Knob and made a 1,000 foot traversing rappel on a near moonless night with one tiny e+lite headlamp. Thankfully we had that one ounce life saver with us.
I have been lucky enough to survive the early stages of my climbing career without any major accidents. When you’re new you don’t even know how dangerous what you’re doing is and in this case ignorance isn’t bliss. Climbing.com has a very good article about 50 common mistakes. It is a good read and worth the few minutes to potentially avoid “building character” through a nasty accident.