Because it's the same old story every season. It's always 'too important'.
A new manager in his first season can't use any kids. A manager in his second season is consolidating, a manager in his 3rd season wants to win stuff to try & keep his job... blah blah.
I can accept it to some extent in a manager's first season. But only to some extent.
After that, it's just utter crap. And has no basis in fact, or history.
Most of the best teams have won stuff & also brought through young players, including Pep's Barca team & also Utd. Two of the most successful teams of the modern era. This is a fact.
There is no 'risk' involved apart from giving up one or two positions on the subs bench sometimes.
It's too fucking easy not to do it, & use this crap as an excuse, is the problem.