It's Chelsea's pattern to be signing many players every season and most of these young lads won't get first team opportunities because of the number of players they've in a particular position. They'll end up being shipped out on loans and some of them will never return back to Chelsea. An example is Kevin De Bruyne. He was signed by Chelsea, only had 3 appearances and was loaned out to Wolfsburg because of limited opportunities. Wolfsburg later made the deal permanent and City clinched him from Wolfsburg and the rest is history.
This new trend of buying more players than they need and giving them long contracts is Todd Boehly’s doing, it is not Chelsea’s pattern. During Roman Abramovich time, Chelsea didn’t make these kind of signings in the transfer window. It’s the change of ownership that has caused the club to reckless and irrational in their transfer dealings.