World building is an unusual combination of imagination and logic. The elements of a world have to fit together in a reasonable fashion that follow an unwritten code of coherence. If the coherence is not present, then the reader cannot enter the world construct.
I use world building for two reasons. First, I enjoy the challenge of pulling a new world together. "Dune" blew my teenage mind in a manner other, more adept, SF writers did not. This new world of Dune told an ancient earth myth with an embracing imagination that still effects my reading.
Second, a world untethered from our reality gives me the freedom to explore characters, ideas, and philosophy without the political ickiness (real word, I swear) that pervades American fiction and alas, non-fiction too. Successful world building makes the suspension of disbelief an easy task for a reader. The character speaks, not the coincidental politics that the uttered words invoke in our current anxious reality. World building is not escapism though, it's separating the wheat from the chaff. It is an opportunity to focus on "the heart of the matter."
Aden is a middle-aged wizard. You may emphasize "wizard" as I intended for presentation, but I emphasize "middle-aged" because, well, it's dogging me these days.