AUSTRALIA - With reference to relevant legal principles using the IRAC legal problem-solving approach to advise Leonard as to whether he would be successful in negligence against Coolies. Please explain fully, using relevant legal authority.

Leonard is 35 years old. He is employed at the packaging warehouse of Coolies Pty Ltd, a successful online retailer. Leonard was injured on his back in 2018 when he was lifting a heavy box to load onto a delivery truck for dispatch. He had to go through spinal surgery and was off work recuperating for nine months. He was fully compensated for his injury and returned to work in 2019. Coolies was aware of the injury and the operation. Towards the end of 2019, Leonard began to complain that his back was getting sore again. He was instructed by Coolies not to lift heavy things and to be careful. Coolies went ahead and provided a hydraulic lifting machine to assist him to carry out his job. After a few weeks Leonard stopped using the machine because he thought it was slowing him down. He continued to lift and load the boxes by himself. In March 2020 online sales drastically increased and Leonard had significantly more boxes to lift and load onto delivery trucks. He injured his back again and once again had to go through surgery. The nature of his back injury has left him unable to lift anything heavy and he is now unable to work again in the packaging industry.