Ask members to play in a competitive game, competitive person uses tactics within the rules to win. Blame person for being hyper competitive.
Your main team leader(Ash) before Nighthaven joins Rainbow dislikes the new members and thinks it is a bad idea. Allow said team leader to create division and conflict with her actions making it a self fulling prophecy but never punish her.
New conflict and division makes original rainbow 6 members start to question the purpose and direction of Rainbow. Old members leave due to previously mentioned conflict, blame old team members (conveniently forget their years of loyal service) and never address one of your leaders poor actions.