More Plumber Mistakes need redoing

Just another avoidable mistake. I am beginning to think these mistakes are being done on purpose. How do you manage to leave the bolts long enough to accommodate the 2 1/8 rise in the flooring but then permanently put the flange on the concrete causing us to have to jack hammer out the concrete to properly do the flange. . Just like being told to install a vanity at 37" and coming back a few minutes later to find it has been installed at 32". Just makes no sense unless it was done on purpose. We shall see! These plumbers were given specific instructions and knew exactly what was needed . No excuse will cover this one.