Heel spur/plantar fasciitis can in some rare cases develop by having an incorrect body stance. Examples of this are driving a car (through keeping the foot on the pedal in an unnatural stance), working squatted down (enormous strain on the fascia) or sitting at a desk with your feet pulled under your chair.
Sometimes easy measures can be taken for this. When driving a car, choose for using the cruise control. When sitting at a desk, assume a correct position.