Alistair Maclean wrote a book about it – which incidentally was made into a movie in 1973.
Kipling wrote a poem about it.
And now Rooney has diagnosed it as the key reason why Manchester United players are not doing their best.
There is an absence of Fear.
Nobody was afraid of Moyes,Van Gaal,Mourinho and Solskjaer like the players in Fergie’s time were afraid of the larger than life Fergie.
“I think the players need to fear someone. They need to fear Ole Gunnar, they need to fear Michael Carrick – they need to respect them but fear them also.The way the game has gone has changed; the society has changed.You’ve got social media. You’ve got players losing a game and then posting something on social media about their new clothing range or aftershave, whatever they are bringing out, which I find remarkable.”(Rooney)

So Solskjaer needs to be able scare his players so that they don’t have the cheek to post stuff about their aftershave etc after going and playing like idiots.
He needs to get some tips from the grand old man of United on how go about getting that bunch of half motivated millionaires on his team to be afraid of him.