How you teach your offenses and defense to your team is more important that X s and O s. Many great coaching jobs without many wins - be realistic if you are smallest school in the conference, etc. You know if you did your best - and got the most out of your material. Must be fun for players. Wince on every mistake.
Players lose confidence - complain only on effort.
They must be able to think on their feet. Success is a lot mental - have confidence once mechanics mastered. Everyone hears your every word. Must develop bench, hopefully 2 deep at every position. If you have even talent, then you can sub more - play until you give up 2 first downs, etc.