It is good rule in life to never to apologize. The right sort of people do not want apologies, and the wrong sort take a mean advantage of them. – P. G. [Sir Pelham Grenville] Wodehouse
If you always put limit on everything you do, physical or anything else. It will spread into your work and into your life. There are no limits. There are only plateaus, and you must not stay there, you must go beyond them. – Bruce Lee