One big reason why the Chicago Cubs Theo Epstein had so much success with the Boston Red Sox was that their farm system consistently produced new talent to go along with their trades and free-agent signings. The Dodgers and Astros are also building perennial elite teams thanks largely to their farm systems. However, the Cubs under Theo Epstein are failing to do this, specifically with their pitching.
Cubs fans would struggle to think of even one pitcher that the Cubs have drafted, developed, and turned into an impactful major league pitcher since Epstein took over as President of Baseball Operations after the 2011 season.