Key players matter. The Golden State Warriors are obviously struggling without their injured star, Stephen Curry. GE (once one of the bluest of the blue chip stocks) has lost nearly half a trillion in market value under less-than-stellar leadership post-Jack Welch. The best talent will often have an out-sized impact on performance in your organization, whether you run a small team or a large business unit.
It pays to pay out-sized attention to the growth, enjoyment, and succession plans for your best people. Can you really expect to do great things without the very best people? A coach with mediocre team talent will likely be perceived as mediocre themselves.