Employees become demotivated when, hired for a role which suggests authority, they have no power.
Employees become demotivated when they are to get permission for even simple things. When they have to wait until instructed, they are made to feel worthless.
They counter this by becoming worthless.
It is not just in an office people stop caring.
Whether at school, at home, in a club, on a team, in a church, when people feel they are unimportant, nothing, no one cares, they stop caring.