Christians: How would you describe wilderness mentality?

This makes me think of the Hebrews wandering in the wilderness for 40 years, all because they started to grumble and lost faith in God. God was there, but they couldn't see him.

Just before they were to enter the promised land they became convinced they could not oust the current inhabitants of the land, even though God told them they could. Their lack of belief in God’s word and promises brought forth the wrath of God. He cursed them with forty years of wilderness wandering until the unbelieving generation died off, never stepping foot in the Promised Land.

Just a guess on my part, but is this linked to "wilderness mentality"? A bit like not being able to see the trees for the wood when you are lost in a forest? Only here it is self-seeking instead of seeking God.