What is your most annoying DNF?

I hope so 

I guess my most annoying one was on "The Wool Trade - Snowshill" Multi 

It was back in the days where I thought ALL caches were at the published coords. I thought a Multi was just a box with multiple compartments 

And even worse at the coords there is a tree, hollow at the back, and spent more than an hour searching, before frustratingly having to give up. Went back a few days later and the same thing happened.

Of course, later I found out that Multi's aren't at the published coords. And when setting, and later maintaining, Snowshill Scramble, I acquired the coords for the final location. An obvious tree.

And a DNF. And another DNF on the maintenance run 

I don't think I'll ever find that cache  Very annoying on every occasion 

Sounds like another excuse of a group trip