This is very simple, but for some evolutionary reason we tend to ignore it.
If you want to get the best out of someone, focus on the subjects he’s good at. Don’t fall in the trap of taking advice from someone who’s the subject isn’t his.
I noticed that I have repeated this mistake over and over again.
If someone is great at marketing strategies, listen to him. He’s more likely to be right than you are.
However, if managing teams isn’t his thing, his advice is useless.
P.S. Everyone is good at something