I agree with @JLeslie—some people just have caretaking personalities. I think they crave being needed and feel fulfilled when they are needed by others. It’s an inherent part of their nature regardless of whether they’re male or female.
Sometimes, yes, I agree that it has to do with control: if I decide what you need and provide it, you’ll depend on me and become unable to do it yourself. However, not all caretakers are control freaks.
My mother’s a big, big caretaker—she started babysitting at age 11 and all of her jobs throughout her life have involved some level of caretaking. She can’t function without someone to care for—and I think that’s okay as long as it doesn’t fall into control-freak zone! On the contrary, even as a mother, I am not a caretaker. I shudder at the idea of being needed—exactly why I teach mouthy high school kids, not little kids that mouth things.