Everyone sins but not everyone persists in sin. Sin is an act of the will. When we sin we turn our will away from God. This we all do from time to time. Afterwards, however, some repent and turn back to God. Others, however, never repent and continue to direct their will away from God. These are the ones that Paul said will not inherit the kingdom of God.
Now you've just made it works based salvation.
Someone is saved as long as they toe the line.
That is NOT salvation by grace through faith.
We don't work to get saved and we don't work to stay saved.
Not all sin is willful sin. There are unintentional sins as well.
But regardless, choosing to sin is not by default choosing to give you your salvation.
Even turning out back on God does not remove us from His family. The Prodigal Son was still the son and welcomed home as a son, even though he didn't have any inheritance cause he blew it. The father never disowned him.
The Book Rome assembled disagrees with you.
Leviticus 5:17-19 Douay-Rheims 1899 American Edition (DRA)
17 If any one sin through ignorance, and do one of those things which by the law of the Lord are forbidden, and being guilty of sin, understand his iniquity,
18 He shall offer of the flocks a ram without blemish to the priest, according to the measure and estimation of the sin: and the priest shall pray for him, because he did it ignorantly: and it shall be forgiven him,
19 Because by mistake he trespassed against the Lord.