Brad, I thought this a good post, because everyones experiences will be different.
1. If coaching, always remember you in fact have individuals who make up a Team. You have team goals, BUT each one of your players have different wants, needs and personalities. You need to establish the types and what works for one doesn't work for all.
2. Absolutely agree with Phizzer and Lockstock. Anything in life is about how hard you work at it. One of the best quotes of all time was from Garry Player (when told after winning a British Open that he had had his share of luck out there on the course), he said "I agree, and I've always found it amazing that the harder I work the luckier I seem to get!!"
3. When coaching juniors, start from the premise you cannot keep all the parents (as opposed to the kids) happy. But communication is the key, involve them in what you are doing and why. Where the kids need to improve, even the good ones. The more feedback provided the more involved they feel, and remember that most parents are living their own non existent sporting abilities through their kids.
Good luck with it.