I don't think you are following. Try geocaching in places like Hong Kong. Its difficult to find the true ground zero. It can be in the basement or 6 floors up! Sometimes the CO wants to make it challenging! The unhappy face remains me that I try finding ground zero. The problem with your thinking, you are taking it too literally of what DNF means. Not finding GZ is a DNF. If you never been in Hong Kong, you have no idea how difficult to find GZ. In most places, GZ is ground level. I got stories of trying to find the true GZ, it shows less than 5 feet on my GPS but I know I was at the wrong level! There was a cache that took me over a hour to get to GZ. Why? Most walkways are on the 3rd floors and trying to find stairways to that 3rd floor can be nerve-wracking because they are behind unmarked doors! A unfounded cache is on my map but it doesn't show if I try looking for it or not. I like seeing the unhappy faces on my map because it reminds me of my journey of trying to get to GZ.
I understand there's other ways to list it but like I said earlier, its more user-friendly to log a DNF log! I am not going to waste my time making a bookmark list! That's too time consuming! I want to turn on my app and see the map and I can see where I left off. No need to fool around looking for the list and trying to get it to work!
If you delete my DNF logs, I will report you to GS! Some people like to see DNF so they understand other people journey so they can make it easier for themselves of not making the same mistakes. They are almost the only thing I read on the cache page.
If you are a CO that hate DNF, you are playing the wrong hobby. DNF is very much part of our hobby. The good CO are the one that don't complain about how other people play the hobby.