They simply do not feel close to God. They understand God as a power and a ruler and the absolute authority. But they do not have a sense of warmth and friendship in their relationship with God. As a result worship tends to be cold. Prayers are empty and more of a ritual.
Prayers seem to be shallow and meaningless.
Doing what God says is more obligation and necessary to avoid Hell than out of striving to please Him. It is hard to get excited about worship when such feelings are held. It is harder yet to talk to others about God when we don't feel that close ourselves. Sin or the guilt of our conscience may keep us from a closeness that we should have. In John 15 we find 2 pictures of a Christian 1.