Well, that's one way. A fascination with the medium is one reason to play around with it, and even if you have other inspirations, it certainly helps.
But sentences are only the vehicle. You can also write out of the fascination with the stuff you put into them, the story -- as a whole, or as a dramatic plot, intriguing characters, a marvelous setting, or even the theme you want to portray, and as inspirations, all these things need only to be wondrous in your own imagination. (Deflating, sometimes, to see what gets on the page.) Sentences are only the way to get them down on the pages -- and it's not the only way. A webcomic can do it without the sentences a writer would, as in this scene, depicting a rescue/escape. A birthday party in their path is an admirable way to have the unexpected intrude on the escape, without making us doubt it (especially since it's not a major twist).
Elegant, eloquent sentences may be important to the writer only as the most effective way to communicate the contents, and many a successful writer has written workmanlike prose -- or worse.
Indeed, John Gardner observed in On Becoming a Novelist that too much verbal sensitivity may make a writer worse, by keeping him from engaging with the story. Scott McCloud in Understanding Comics differentiated between artists whose great interests were with technique, and those whose were story, and even observed that the latter are often technical innovators, shaping techniques so that they expressed what the artist needed to express to tell his story.