Every stable of a Major League team is their goal in trying to develop minor league players acquired in the rule four draft, international free agency, or trade to supplement their roster; whether that supplement is from them being called up or being used as trade currency depends on the current state of the 25-man roster. Teams like these young players as they are both cost effective and are under team control for up to six (or parts of seven) seasons. The theoretical goal is these players can supplement the current core, or a team can supplement a young core by spending money in free agency.
Pittsburgh Pirates: How Teams Fare With Player Development
