The secret of the executed general

Army General, Hero of the Soviet Union Dmitry Grigoryevich Pavlov, is one of the most iconic figures of the first months of the Great Patriotic War. Having commanded the troops of the Special Western Military District, he met the first, most powerful and crushing blow to the Nazi forces in their main direction. Let the army units subordinate to him defeated, but committed everything possible and suspended the movement of enemy troops for several weeks, which allowed the General Staff to regroup forces and prepare for defense. General Pavlov was shot on July 22, 1941 by the verdict of the military tribunal. But what are the real causes of severe reprisals against a good commander?