This should be apparent to anyone with common sense or someone who's actually experienced a proper workplace. In no organization, will a new guy just jump up the pecking order over more experienced pros until the performance of the older guy is really bad. You have to the manage the older pros as well and if the performance of the younger players makes them impossible to drop, then they'll stay in the team, otherwise they'll be integrated slowly.
People compare Lampard with Ole and how he's playing the kids, all of Chelsea's kids are 21, ours are 17, 18 or 19 year olds. People need to have patience.
For every Rooney or Ronaldo, who excelled after being thrust in as a teenager, there's a Januzaj or a Wilson who suffered from being thrust into the first team when they weren't totally ready for it.