Grace is undeserved.
Are we sinners saved because we are better than everyone else? Are we somehow greater because a sovereign God chose us from the foundation of the world to be His own?
Quite the contrary.
The word "grace" is found in the Bible 124 times. This is how badly we need God's grace.
The saved Christian does not become sin free once they believe and trust in Him alone for salvation, but the Christian life is a constant, uphill battle. Disappointment, grief, pain, are all things we still face, and will continue to face until we go to be with The Lord.
The most important thing to understand about grace is that God's grace is what has saved us from our sins, and it is not anything that we have done. Not the slightest iota on our part contributes to our salvation. (See Ephesians 2:8-9.)
As we struggle in our uphill battle day after day, we constantly let down our family, friends, and the One who sent His son to shed His blood for us.
Why are we forgiven as many times as we sin? God's grace.
Grace is not merit, it is not earned, nor is it deserved. We receive God's grace only because He chose to love us, and sent His son Jesus to pay the penalty for our sins.
We are weak. He is strong.
We sin. His grace forgives us.
We deserve Hell. God gives us life.