When setting a goal, define what level of performance of achievement you want to reach to feel satisfied with your efforts. If after a realistic period of time your performance or achievement leaves a lot to be desired, perhaps you should re-consider again.
“Reasonable” and “realistic” are key words here.
Consider that sometimes progress doesn’t happen for a long time, and then everything changes virtually overnight. You need to account for this fact before you decide to forgo your efforts.