Tourniquets are no longer a “last resort” option and have a number of uses. Their primary purpose is to buy you time until you can control bleeding with well-aimed direct pressure–though in some cases you might be unable to get that in which case the tourniquet stays on. The mindset about tourniquet removal has definitely changed though. A use case for a tourniquet might be that you put one on as a hasty intervention to stop bleeding until you can get to a safer location. We have also used them during wound cleaning on extremities–it keeps the wound clear of blood and numbs the limb (wound cleaning can be an “uncomfortable” process)–they are used in surgery specifically to keep the surgery site clear of blood. It is one piece of equipment that can significantly change the outcome of an injury and one that is challenging to improvise correctly. Plenty of science backs up the efficacy of quality commercial tourniquets. Good training helps you know when to apply it.