Lampard was tipped to be a successful coach based on his performance in Derby County but his time in Chelsea and Everton was not successful. Rooney had an even worst career since he has not been successful in the clubs he has handled.
The way you view football matters a lot when it comes to the success of a coach. Bayern were able to trust a rookie coach like Kompany because of the way he sees the game and he sees the game that way because of the person he played under. He has the idea of Pep and Pep's idea is something that Bayern Munich wants.
Rooney on the other hand sees football like Alex Ferguson and to be honest that may be an obsolete way of viewing the game and that may be why he has not had success in any team he has coached.
Coaching is a very complicated job so it requires a whole lot. It takes way more to be a successful coach than to be a successful player. I respect good and tactical coaches a lot because their job is not an easy one.