How we read the wall before drilling
Masonry is not one material, and the first ten minutes of any stone or brick job are spent figuring out which one we are actually looking at. A tap test tells us whether the face is solid or a thin veneer panel over framing. Looking at an outside corner or an edge near trim usually shows the veneer thickness. A small pilot hole in an inconspicuous spot confirms the depth of solid material behind the surface.
Only after that do we pick the anchor. Guessing is how brackets end up in a half-inch of veneer with nothing behind it, and it is the reason we would rather spend ten minutes probing than come back for a fallen TV.