When I was a teenager I went to Yosemite with my family and a good friend of mine. We decided to hike up to Vernal Falls, which has a relatively easy path up. On the way up my buddy and I found a small path that also went up, but broke off from the main trail. We took it of course, being kids, and about a thousand yards or so up, the path began to narrow. My buddy went back down and then up to the main trail. I decided that I didn't want to have wasted my time, have to go back down, and then rush to catch up to my family, so I continued on.
Not to much farther up the path narrowed to about a hands width, angled slightly down and then just vanished. If you've ever hiked to Vernal Falls, you know the path in question borders the river that is full of boulders. Falling in would be death. Being young and stupid, I did the dumbest thing of my life and looked up the cliff to the main path. It was only 12-15 feet up and there were handholds and footrests all over. The cliff, though, was not straight and what I did not realize until after I had climbed halfway up, was that the cliff smoothed out for the second half of the climb.
So here I was hanging off the side of the cliff and those hand and footholds I used to come up were very small, so going back down meant I was likely to slip and if I slide onto the hands width that was angled down, off I would go. Looking up again I notices some grass growing here and there in the cliff face. I grabbed one tuft of it and pulled. It held and seemed like it would support me. So being that immortally stupid teenager, I held that grass and used the remaining body length of hand holds as foot rests. I'm here typing, so the grass held. When the foot rests ended I was at a point where I could reach over the top of the cliff and I pulled myself up to the main path.