I was thinking about buying a wurkkos fc11 as my first flashlight but it said they recommend untwisting it in a review to avoid making a connection so it doesn’t discharge while not in use. Do I need to worry about that with all flashlights? I was planning on keeping it in my backpack so I have it whenever.
There are two issues: 1) parasitic drain from the light itself, 2) inherent self-discharge of all rechargeable batteries (Eneloops seem to have this the least). If you want an emergency light to keep unused in your kit for years, get one with mechanical switching (battery completely disconnected when light is turned off) and put in a lithium primary (non-rechargeable) battery. Those have the longest shelf life and also the best performance in very cold or hot weather. For a frequently used light, use rechargeable of course, and charge it up once in a while.