Do sheep and concrete floors have anything in common? Well, probably not on face value.
But think about sheep for a moment. They are covered in wool. Wool is a porous and bulky material that provides a physical avenue to draw moisture (known as moisture transmission) away from the sheep's body and for whoever might be wearing the sheep's wool.
Now think really deep about concrete and you might remember that concrete is a porous material too, and it can behave like a dense sponge. In the case of water, that "sponge" not only absorbs water from the surface but it can absorb water from the ground, too. Moisture in or below a concrete slab allows the concrete to move moisture through the concrete in a process very similar to the sheep's wool. In the case of concrete it's called moisture vapor transmission. And this can cause floor coating adhesion problems.
The flow of moisture vapor transmission from excess moisture in or below the concrete slab is the cause for a large percentage of floor coating failures.
A moisture barrier below the concrete when it was first poured could help prevent this problem. To solve this problem after the concrete is poured requires a respirable floor coating that allows the concrete to breath and allows the moisture to move to the surface without affecting the adhesion of the coating.