I don't think it's necessarily emotional. The world does not have set inputs and outputs, and effort can be expended on activities that turn out to be arbitrari

I don't think it's necessarily emotional. The world does not have set inputs and outputs, and effort can be expended on activities that turn out to be arbitrarily fruitless. Decoupling expenditure of effort from expectation of reward would naturally and logically reduce motivation for even logically-deduced need. I think trauma and disappointment are far more prevalent than true sloth or vice, if such things as the later two exist at all.