I Thessalonians 4:3
That every one of you should know how to possess his vessel in sanctification and honour.
Part of self-discipline is knowing what pulls you down, and what encourages you to do right. If you find yourself being pulled away from your focus, stop and ask God to help you get back on track. People who are really serious about their goals and commitments will become accountable to someone that will hold them to their word. Do you know where you are weak and need help?