You coach individuals, not teams. If you can do this, a side will emerge. Players are inspired by confidence in their coach. Great coaches inspire them to have confidence in themselves. Winning breeds confidence, and confidence breeds winning.
Confidence is contagious.
So is lack of confidence. Courage is resistance to fear, mastery of fear - not the absence of fear. Only those who dare to fail greatly can ever achieve greatly. Find a remedy. You find out when coaches start running other people down, they are telling you something about themselves.