I try to teach. . . if you don't see it or hear it go down, wait at least 30 minutes.
Take a compass reading on the direction it ran and memorize it or write it down.
If you believe you made a less than perfect hit ( to far back, bad sign like green etc)wait, then get your stuff quietly out of the woods and go somewhere else to think.
Unless it is really scared, like, a bone was hit or broken, or a huge noise was made, a deer will likely run a distance, around 100 yards in normal woods, then stop in a thick area and turn to watch its back trail. If you are not following, or not jumping up and down and doing high fives with your camera man and telling how you "smoked " this one ( Sorry. . back down off of my stump)it will likely bed down nearby. Given enough time, it will expire there.
If scared, a deer is more likely to run and run.
Heart shot deer often run hard till they drop, and that could be several hundred yards. How long does it take a deer to run several hundred yards ? Not very.
A measuring stick oftens does help a lot. I have been in places where they are not a lot of use, and others where without a doubt they can show you where to look for the next sign.
ChuckC