In-hunt Mentality
You must keep the same anticipation you had when you first got into the stand when the woods were dark and quiet. You knew you'd see a deer near first light. As time passed, you started to doubt that you would see a deer. You relaxed and the deer won.
How is it that they sometimes appear from nowhere, especially from where you thought was downwind? You didn't see or hear anything (did you?). Don't forget that you're dealing with the magical forest creatures known as "deer." If you don't respect the whitetail you will not get the whitetail, especially on those challenging days.
You must always believe that a deer is just beyond you; that it is close enough that it can either see or hear you. If you do, you'll behave accordingly, and not fidget, make noise or fall asleep. You need to be on watch the whole hunt, skillfully scanning in front and behind. You need to be ready, able to draw or raise your weapon at a moment's notice. If you are not doing these things, you are missing deer!
That's hard work, especially for all-day sits in cold weather! It takes a mental toughness to put your beliefs into action and keep with it all day. Today I got lackadaisical in my approach to the deer. I missed probably 7 opportunities that could have paid off had I been on my game. We all have bad days, but on a day with so much opportunity, you have to learn a lesson. The lesson?
You got comfortable.