As mentioned in a post two weeks ago, I've been reading Andrew Roberts' incredible biography of Winston Churchill. At one point, Roberts describes Churchill's appointment of Alan Brooke as Chief of the Imperial General Staff during World War II. Roberts writes:
As we have seen, one of the most useful insights Churchill gained from the Great War was the phenomenon he had seen in Haig's Intelligence Department. 'The temptation to tell a chief in a great position the things he most likes to hear is one of the commonest explanations of mistake policy,' he had written. 'Thus, the outlook of the leader on whose decisions fateful events depend is usually far more sanguine than the brutal facts admit.' Churchill therefore appointed men like Brooke and Admiral Sir Andrew Cunningham, who told him exactly whaat they thought he needed to hear. Brooke did not seek out confrontation with the Prime Minister, but neither did he shy away from it. He tended to choose his battles carefully, not opposing him on trivial matters. He was to tell Moran that 'every month' of working with Churchill 'is a year off my life.' Earlier in 1941, Lord Vansittart had told the newspaper editor W.P. Crozier that 'Churchill needs people beside him who can say quite firmly "No" when he wants to do something wrong and insist that he must not do it. Such a man was Brooke, whom Churchill respected and whom he knew would not allow him to repeat such errors as Gallipoli or Greece.
That's a fantastic story of the rationale behind a crucial appointment. Every leader should reflect upon this story and learn from it.