There are many reasons to hire a coach, but there's only one #1. This story says it perfectly.
Rick and Carole are standing on the 18th tee at their Country Club. They are the final twosome in the Country Club Championship and are tied for the lead. The 18th hole is a beautiful par four with a deep valley descending down to a dogleg right.
Both Rick and Carole hit long, straight tee shots which disappear down into the valley. A short time later, the fore caddie appears at the top of the hill and announces that both balls are within a foot of each other, but there's a problem. Both of the golf balls are Titleist #4s.
Rick and Carole look at each other and realize that they had not informed each other as to what kind of ball they were playing, nor its number. They quickly descend into the valley and, sure enough, their two Titleist golf balls are right next to each at the bottom of the valley in the middle of the fairway.
Carole looks at Rick and says, "We had better get a ruling from a tournament official to straighten this out." "This is the Country Club Championship and we don't want to be disqualified for making a mistake and hitting the wrong ball." "After all, we are tied for the lead."
Soon after, a rules official appears and examines the two #4 Titleist golf balls. He then looks up at Rick and Carole and asks, "Which one of you is playing the orange ball?
The #1 reason to hire a coach?
Your coach will be able to see the answer that you cannot, even though it's right in front of you.