If you compare yourself with someone who is smarter, more talented, or more physically attractive, you look inferior. If you compare yourself with someone who is less intelligent, less talented and less attractive, you feel superior.
If you compare yourself with yourself, you feel good. Yet you are the same person in all of the comparisons. If you want to have a true measure of yourself, measure yourself by the true standard: the Word of God.

Let a man regard us in this manner, as servants of Christ, and stewards of the mysteries of God. In this case, moreover, it is required of stewards that one be found trustworthy. But to me it is a very small thing that I should be examined by you, or by any human court; in fact, I do not even examine myself. For I am conscious of nothing against myself, yet I am not by this acquitted; but the one who examines me is the Lord.
1 Corinthians 4:1-4

For we are not bold to class or compare ourselves with some of those who commend themselves; but when they measure themselves by themselves, and compare themselves with themselves, they are without understanding.
2 Corinthians 10:12