There’s plenty of information on the operating limitations of an airplane. A VG diagram (in some applications called a VN diagram) shows many things including stalling speed, maneuvering speed, maximum allowable speed, maximum indicated airspeed in rough air and maximum allowable G loading, both positive and negative. Operate within the parameters of the VG diagram and you are flying the airplane within its envelope. The closer you fly to the edges of the envelope, the lower your margins.
Pilots don’t have to learn to read VG diagrams because this information is shown in other ways. Airspeed indicator markings and operating limitations provide the information that we need to operate within the envelope.
