RE: What is the worst thing that has happened
Don't feel too horrible. As long as you put in the effort and learned from the experience. It sucks but the coyotes or whatever need to eat too. The same thing happened to me last year for the first time. I looked for several hours that night and all day the next day. Never did find it.
I've never had anything too terrible happen yet such as a fall or accident, but last year, the neighbor's dog did tear into a doe in the 30 minutes inbetween when I climbed down and went back to the house for my game cart. Lesson learned there. Don't dawdle in such a situation. Just get back there and get the deer before a coyote or neighbor dog digs in.
The other bad experiences have involved trespassers screwing up hunts. I usually have some fun by blowing grunt calls at them, though, and watching them stalk the phantom buck. lol. Good stuff.