Note log is another option
Sometimes, when it's not a true DNF, I will log a note if nothing more for my own reference. Did this just yesterday as we were going to do a cache on the way through to Waterville. by the time we found a parking spot close enough, it was too late to walk that distance and we were still unsure it was the right starting point. So, I logged a note. If I want to remember when we were there, I have a record of it now, and the cache owner knows someone was at least considering the cache that day.