This is an easy question to answer. When you watch a snow leopard hunting on the steep, 40°, rocky slopes of its high plains habitat and mountain landscapes you will see his/her tail swishing from side to side as a counterbalance to the cat’s sharp, twisting movements as he chases down a blue sheep, his primary prey.
The cat’s tail assists balance. We know that. The snow leopard has a particular need to maintain balance which is why the snow leopard’s tail is the thickest and longest (as a combination) of all the wild cat species. This is no surprise. Just watch a video of a snow leopard hunting amongst the rocks and mountains of its magnificent habitat.
If you stand on one leg you have to maintain your balance. If you wobble slightly you will move your other leg outwards or to one side to counterbalance your body and thereby retain balance. These are the same principles, with respect to the physics, as the use of a snow leopard’s tail when hunting.