When I was a young designer I concentrated too much on wowing the client, user, etc… What I failed to realize is all the decoration that I was adding to a design actually interfered with the effectiveness of the design.
Part of this was because I tried to get the design to look “impressive” which to me, meant adding a bunch of frills that really didn’t fit the communication of the design. Every element, line, dot, color says something. It says something beyond “wow that looks nice”, whether you realize it or not.
That is why it is important to pre-establish the voice of your design. The design should communicate a message and you need to be aware of that message. Otherwise you will simply be creating design elements for design sake, rather than communicating a message. The end result is that you communicate the WRONG message, and the design will fail.
Think about each element, is it consistent with the voice of the design? Does it fit?