Locklear makes the dirt hole facing the travel way in the traditional up wind location and places the trap behind the backing/hole because that is where the animal will go once they recognize/see the hole while going by. It also depends how you lure the set. If your lure is down the hole the canine might not smell it from behind but if you lure the set by placing the lure on the lip of the hole, as some do,
If the the animal can leave the trail and circle the set close enough to get in that rear trap; the set is at a poor location.
Now think about this and study about it for a few days- but
Why do you make a hole if not to conceal the bait/lure and direct the animal into the trap?
If I want to distribute the scent in many directions, I put it about 4' high and 10' away from the set. if I want to catch an animal I put the scent/bait in a place that can only be approached from one single place/direction- this takes a couple minutes of planning, maybe, but if you chose to set an open in all directions bait with zero guidance, then I would suggest ten or twenty traps arranged in a complete circle, because if the animal approaches from some direction than the "front" you can not guess what direction that will be. Setting the trap at the "rear" of the hole simply means the hole has no "front" because you made it frontless on purpose. That is a wasted hole. It tells the target "go any where, I don't care to trap you".
Coyotes, fox and bobcats are not mink, they do not investigate holes just because they see a hole, at least not in my patch- this country is chock full of abandoned woodchuck holes and armadillo holes and holes and holes, and very often more holes; these stupid animals here never got to watch any videos either so they never learned that they are are supposed to reason like humans. The only reason I ever make a hole is to use as a guide and a cache. But iI have no videos to watch and none to sell either.
The best hole I have used is mouse sized either on a bank/slope or under something like a stump,rock, bale, etc.- with all those big holes I have I have never found a cat or coyote track near any of them.