I have a question: The Bible says that we don't deserve anything. Then why do people say, 'You deserve that achievement' or 'You deserve it'? Isn't this wrong?
First, I can't recall any passage that says we don't deserve anything. It is true that we cannot earn salvation (Titus 3:5-7), but that doesn't translate to all aspects of life. Instead, the Bible states that what you put into life affects what you get out of it.
"Therefore they shall eat the fruit of their own way, And be filled to the full with their own fancies. For the turning away of the simple will slay them, And the complacency of fools will destroy them; But whoever listens to me will dwell safely, And will be secure, without fear of evil" (Proverbs 1:31-33).
"If the righteous will be rewarded in the earth, How much more the wicked and the sinner!" (Proverbs 11:31).