You dont know what you don't know
I would be willing to bet that the folks saying that instructors are a waste of money have not taken a lesson from a certified master instructor. There are so many good players who think they can teach and many of them give quality instructors a bad name. Unless you have taken lessons from several top notch instructors, I'm not sure how you can make an objective opinion on the effectiveness of professional instruction. There are way more good players than there are quality instructors. I have not talked to anyone who has taken lessons from a certified master level instructor and said it was a waste of money... Most say it was worth way more.
I would be willing to bet that the folks saying that instructors are a waste of money have not taken a lesson from a certified master instructor. There are so many good players who think they can teach and many of them give quality instructors a bad name. Unless you have taken lessons from several top notch instructors, I'm not sure how you can make an objective opinion on the effectiveness of professional instruction. There are way more good players than there are quality instructors. I have not talked to anyone who has taken lessons from a certified master level instructor and said it was a waste of money... Most say it was worth way more.