If the buck you are after spends a morning chasing a doe around your stand but never stops or even slows down enough in a spot where you can shoot him, how is that a failure of yours? I would personally chalk the experience up as a success with some bad luck mixed in.
Just because you failed at filling your tag by no means your season was not a success.
In my situation....I can only say that if I don't kill a mature buck this year.....it'll be because he isn't there.....or he doesn't offer me the opportunity. I'll be out there.
I have set a personal standard that I will adhere to. If I come up at the end of the season.....and haven't filled a buck tag.....you can rest assured that the deer din't show up. Like I said.....I'll be out there....doing what it takes (both pre-season work and spending time on stand).
I hope to not have to make such a statement.
Two more excuses

Jeff they are there, you just have to find them.
If the buck you are after spends a morning chasing a doe around your stand but never stops or even slows down enough in a spot where you can shoot him, how is that a failure of yours?
Who's fault is it if there is a stiff breeze blowing to the outfield and a pitcher gives up a homerun to a hit that in normal weather wouldn't have made it to the warning track?
The pitchers!