Design involves removing the unnecessary so that the necessary is absolutely clear. Though decoration is important, and an aspect of design, it is not the primary aspect.
Details
Anything that is not a useful part of your story should be eliminated.
Simple messages cut out all the stuff that doesn’t matter. Everything is there to get the point across, and anything else that’s a distraction is vigorously stripped away. Empty platitudes, useless fluff, anything that isn’t a necessary component of your story is another place to lose the receiver. You have only a small window to be heard, so don’t waste it. Design is not the same thing as decoration. Decoration is adding ornamentation to “pretty things up