Within the field of instructional design, we have sometimes observed a hesitation to dwell on visual aesthetics (Parrish, 2009). This hesitation may stem from concern that artistically-approached designs will lack the ability to be replicated (Merrill & Wilson, 2006) or that the artistic elements will serve merely as window dressing—or worse, distraction—that provides no educational benefit to the learner.
I find this to be true in my experience. I have worked with some professors who baulk at the idea of spending time creating or searching for a course banner image. There's other examples related to this, but I personally think that something as simple as finding or creating a course banner image can excite students. Or, if it's a corporate training hosted through Rise or Storyline, this may just be little visual elements and images that add a little something to the visual experience.