Natural light is great, but the sun sets!
Your flash is on as long as your batteries are charged!
Imagine tho, if you could have the sun on a stick and choose where you want it to be, to light up your subject; how great would it be to control where you want your light to be coming from?!
Sure, there’s a bit more to it than that, but when you start to think of it like “the sun on a stick” it no longer seems as daunting to tackle.