Learn from everyone. Guitarist Tom Morello (Rage Against the Machine) explained that five things destroy your band.
I'll use this mnemonic: M O M E S
The five destroyers are:
MONEY
OTHERS - significant others
MENTAL HEALTH
EGO
SUBSTANCE ABUSE
Money. "Money" includes compensation like roles and recognition. I've harped on Chuck Daly's "48 minutes, 48 shots, 48 million." In some programs, parents track minutes and complain about coaches promoting some players over others.
Others. Others include friends and family. How many families have said, "She's not all that. You're every bit as good as she is." You've heard it; maybe you even said it.
Mental health. The physical and mental changes of adolescence challenge many adolescents and young adults. Coaches may sense something is off but be unaware of depression, anxiety, attention and learning disorders, compulsions, or even personality disorders. Dual diagnoses combine behavioral health problems with alcohol or substance abuse. Unrecognized and untreated mental health problem impact performance as much as unseen physical problems.
Ego. Erik Spoelstra's quote is notable, "there is always a pecking order." Competition for roles and recognition can fragment a team. Jealousy can create cliques and some players even refuse to pass to rival teammates. Sometimes the star player gets viewed as arrogant and on girls teams, she can get an undeserved reputation as a 'b*tch'. Coaches, especially men, may have no idea of the social dysfunction in the locker room.
James Hetfield of Metallica says that forty years together has brought the group to understanding a simple question, "what's best for the project," which quells ego. "We'll find another place for your riff."
Substance abuse. This includes alcohol and drugs. I played a game in high school where a star player was partly intoxicated. And I've seen games where significant players were on suspension for violation of chemical health policies. Alcohol even days before competition degrades learning, memory, and recovery. "A single night’s alcohol use impairs hydration (alcohol is a diuretic), muscle recovery, healing, and can cause memory deficits for three days." Moreover, it shows immaturity and selfishness with no regard for the team. "But everyone does it" is unacceptable and inexcusable.
If you've coached for awhile, you've experienced all of these. And there's a good chance you've played and seen more than a little. Coaches suffer the same problems, too, including problems for other jobs and family issues spilling into our coaching. Nobody is immune.
That's not saying other things can't or won't go wrong - health, injury, poor performance, bad luck. Still, the Morello five have a lot of 'control what you can control' elements, mental health aside.
Lagniappe. "When asked, Is beer good for runners?, running legend Jim Fixx’s answer was “Sure, if it’s the other guy drinking it.” If you stay sober, you can take advantage of other athletes’ poor judgment!"
Lagniappe 2. What about the NCAA and mental health? The NCAA is talking about it more, but both male and female athletes surveyed said the NCAA isn't doing enough. "Women viewed the NCAA’s approach to mental health more negatively than did men: 23 percent of male respondents and just 13 percent of female respondents said that the association provided enough mental health services. The allocation of resources among male and female athletic programs may have affected these results."