On my elk hunt last year in CO, I had a 5x5 at 17.5 and 2 cows at 17.5 and 20 yards. The bull was behind the cows at 30 yards - saw his legs, never saw what he was at 35 yards. All 3 between 11-2. I wasn't ready for any of them. Rookie elk hunter move.
The following day, we chased a monster up the mountain. We had him coming to the call, so I set up down a ath under a tree with the thought he'd step into the opening about 20 yards from me and I'd have a great shot on him. Instead, as I looked around, I realized the tree I had set up under was at the convergence of 3 paths - 2 of which I had a shot, one was no shot. At 11:15, he came down the path I had no shot on and stopped 4 yards from me. I was at full draw, trying to figure out a way to release my arrow and get it to make it through some branches and brush. Decided not to take the shot. Afterwards, my guide asked me if I saw him. I said I didn't, just saw his hoof. He proceeded to tell me he stepped to the top of the opening and was a massive 6x6 with dark chocolate antlers. We had seen him the day before from 800 yards, so I knew the one.
Point is just because you think they aren't moving doesn't mean they aren't. That's one thing I didn't like about the guide I went out with last year. They hunt from about 6:30am to 11:30am, head to camp and go back out around 4:00pm to dark. I'd rather be out there all day.