You can have a high IQ, and yet be a slacker in life.
Why? Because IQ is still only a potential of the brain… not independent of what you use or not use, what you expose yourself or not…
I once had an employee who I hired because she was a Mensa Society member. Mensa only accepts people to be members whose IQ tests say they are above 130… I think. But, between you and me, she was a useless employee and I had to let her go.
Since then I don’t trust IQ tests. You can have a high IQ, and yet be an underachiever in life.