You will never know what you could have accomplished if you hadn't stepped out. At least while failing you experienced it.
"It's not the critic who counts; not the man who points out how the strong man stumbles, or where the doer of deeds could have done better. The credit belongs to the man who is actually in the arena... who, at best, knows in the end the triumph of great achievement, and who, at the worst, if he fails, at least fails while daring greatly. So that his place will never be with those cold timid souls who know neither victory nor defeats" - Theodore Roosevelt.