Much of our industry focuses on identifying winners, whether stock picks, asset classes, managers, or strategies. We could eliminate a main source of implementation shortfall, however, by spending at least as much effort on identifying and purging losers. Also in need of our attention are problems or practices that exacerbate the effects of chasing winners, including agency effects that encourage comfortable, not profitable, investing; ignoring hidden costs; holding cash reserves; and allowing inertia to inadvertently change the asset mix of our portfolios.