Though the leadership qualities required at one level of command may result in promotion, they are often not those relevant to a higher level of command. Just as a brilliant general, such as the Australian Sir John Monash, may have been an indifferent brigadier, mediocre battalion commander and third-rate platoon commander, so, more seriously, there have been outstanding platoon and company commanders who, promoted on the basis of their performance at these levels, ended up as inept if beloved generals. Such examples of the Peter Principle, wherein people are raised to their own level of inefficiency, was never better illustrated than in the case of Sir Redvers Buller, who has been described as ‘a superb major, a mediocre colonel and an abysmal general’.

Norman F. Dixon, On The Psychology of Military Incompetence (1976)