It might be that you are new to snowsports and wanting to learn what gear you like prior to making a purchase. You could also be a more experienced skiier, wanting to try something new or wanting gear right sized for the current conditions. If you are travelling some distance, renting equipment and gear on mountain is more convenient and cheaper than lugging weighty equipment around. As a parent of a child that is simply growing too fast, renting could be an option rather than investing in gear that they will soon outgrow.