Draft and Follow
A player is drafted, usually the second day of the draft, and the team doesn't have room for him in the minors, or they think the player need to mature a little more (physically, for example). Because they own the player till the next draft, they follow the player's developmen and sign him before the next draft if they believe the player has reached the expectations. If the player is not signed, he may get back to the next year draft.