"From each according to his ability, to each according to his needs" - sound familiar?
So, if you're having a bad day or you ability is to sit around getting high and watching the tube, then that's all the state can ask based upon your abilities. But, your needs still dictate that you need shelter, food, energy, clothes, transportation, health care, etc... and someone with abilities needs to provide all that for, essentially, free compared to what a lazy POS is putting into the system compared to what they're getting out of it.