A crown signifies a reward for doing something that is right. In scripture, we can see this illustrated in a number of passages:
1 Corinthians 9:24-26 (KJV)
24 Know ye not that they which run in a race run all, but one receiveth the prize? So run, that ye may obtain.
25 And every man that striveth for the mastery is temperate in all things. Now they do it to obtain a corruptible crown; but we an incorruptible.
James 1: 12
Blessed is the man that endureth temptation: for when he is tried, he shall receive the crown of life, which the Lord hath promised to them that love him.
Sacrifice is a step beyond convenience. Bill Johnson