sounds good, but realistically, there is never just a single goal, and all goals have to fit in with the true over arching goal of how to live better and be happy.

Or when your single mindedness hurts others you either care about or should care about. This is where we all fall down

Your goals are never just yours alone in a vacuum.

But yea, if you have a worthy goal, I’d say the fear of failure or just plain laziness are your worst enemies to success, you recognize those by procrastination, indecision, or lack of persistence.