A rebuild is a deliberate period in which a team gives up on contending now, trades older players for draft picks and young talent, clears salary and plays its prospects, with the aim of being good again in a few seasons.
In HoopSim a rebuild is both a human strategy and an AI one. Every AI GM has a plan for its team, contending, retooling or rebuilding, and The Rebuilder persona lives there ("tearing it down to build it right"); rebuilding AI teams value picks and young players and list veterans on the trade block. For you, the tools are the same: picks tradeable three years out, the Stepien rule, minutes that develop young players fastest, training camp focus, extensions for the ones who pan out. Mid-season trades and a roster full of new faces cost chemistry, which recovers as a core stays together.
Rulebook: AI GMs. Related: tanking, salary dump, dynasty.