Young mechanics, especially men, are prone to overtightening everything. Too much torque is dangerous, as everyone learns sooner or later. The snapped-off bolt or stripped-out screw head is a real motherfucker, and you have no-one to blame but yourself. Now you learn the art of extraction, which is an opportunity to do some real damage if you’re not careful. Some fittings need to be tightened to specified torque and need a torque wrench, but for most of the bolts and screws you’re installing, you need to develop the feel for getting your fasteners mechanically tight. Not Grape-Ape tight. It is a feel, and it takes practice to develop. You will screw it up sometimes, so, yes, extracting broken fasteners is another skill you need.