Turned back or bailed out a few times. There is one hike in Big Bend Ntl. Pk. that is only 36 miles (Outer Mountain Loop) that is, for some reason, a butt kicker. It's common to bail at the 2/3rds point, which is as close to a road as you'll ever get, and hitchhike back in. Blisters, water, and a fire made us terminate that hike before.
Also, kayaking rivers where the dams decided to stop generating and left us high and dry, forcing a bailout or long wait.
Hiked/skied a glacier in Switzerland that turned to slush that forced a different route.
Same thing in Canada where ice was soft and dangerous.

Not turning back gets people killed in airplanes and boats all the time. Best go back and live to try again.