When you keep making the same mistakes over and over, and you keep saying, "you know I'm not perfect", that's the devil beating the drums of destruction for you and you're ignorantly dancing to it! That's why people ain't getting any better or even make efforts to get better!
We must learn to take responsibilities for our actions/mistakes, accept that we're wrong, learn from it and determine to get better- that's the only way to walk in CHRIST'S perfection! Here's what our LORD JESUS said in Matthew 5:48, " You therefore must be perfect, as your heavenly Father is perfect."
So, stop believing those lies. That's part of the devil's tricks to keep you down in his claws for life. Don't allow it! Determine to be perfect just like JESUS!