Our old nature is still in us and some part of us still wants to rebel
Original sin, is the short answer. Due to our inherent imperfection and the sin nature, we will always “instinctively” turn to self. Satan wants nothing more that to watch us fail to cast our cares on the Lord and to wallow in self-centeredness.
We are, at our root, sinners. We will always struggle with the desires of our flesh. We naturally tend to want to suppress the truth deep within our hearts. Original sin is where this all began. But through Christ and with the Holy Spirit’s counsel and direction, we are ultimately sanctified through the grace of God.
Since we lived most of our lives and spend time with people and family members with self centeredness it will take time to make a change. But with studying God’s Word and drawing closer to Him we start to let go of that self centeredness little by little through faith in Jesus Christ and the leading of the Holy Spirit