First, you have to (or at least - you had to). I mean, it was the only way to sanely include a lot of formulae and managing bibliography.

Then you discover that is id beautiful. Honestly, even using base style sets you above the typesetting of books. With some extra tweaks, it is beautiful.

Did I spend a lot of time on LaTeX during my PhD. Sure! But (even counting in all masochism involved into dealing with LaTeX) I both cherish this time, and the results.