I've mentioned my low-maintenance hair routine a lot: I don't dye it, I rarely use hot tools and mostly air-dry it, and I keep it minimal with my products. Even though I
don't fuss with my hair that often, it can still get dried out. When my hair starts to get trapped in a vortex of static cling, that's when I know it's in need of some hydration help.
A lot of different factors can cause dry hair: overuse of heat tools (especially without using protectants), washing it too much, hair dyes and bleaches, using the wrong products, and the environment/weather. You can do the bare minimum to your hair and still get some dry strands every now and then. For me, I think it's caused by environmental changes—it tends to feel drier in the winter months.