ChuckC nailed it.
I would like to add one thing from my observations. Look for places that are "focus changers" for the deer, and try to construct your shooting lane for this spot.
For a deer, the creek is a natural "focus changer." Regardless of the deer's concerns, say being slightly on alert because of a little noise or movement, the deer will change his focus when he decides to think about how to cross the creek. At that point, the deer's alertness leaves and he's relaxed with new Priorities.
Actively getting busted is one thing. Having a deer jump your arrow is also "getting busted." And, I'm convinced they need these "focus changers."
I had a red fox dart in front of a buck this year: focus changer. I had a doe, very nervous about me in the golden rod, become completely relaxed when she put her front feet in the bean field and look at a yearling. She stopped and changed her focus to "feeding time." On the other hand, I had a buck jump my arrow even though he was looking away and didn't really know I was there (but, he was obviously on alert about me tucked against a rock pile).