Some ways that a delivery or body communication can contradict the message of a speech are scenarios in which the speakers tone, clothes, or inflection are inappropriate for the scenario. For example, a speaker at a funeral, where the mood should be somber and memorial, wearing bright, flashy clothes and acting happy about the occasion will most likely not relate to the attendees who are grieving the loss of a loved one.On the other hand a speaker who dresses in dark colors and appears to be mourning will not relate to an audience that is celebrating an achievement at work or a birthday party. The impact of these contradictions could lead to the audience shutting down and not giving the speaker their time.
Seeing a guy in a goofy outfit at a funeral would definitely throw off the vibe and I am sure that not many people would appreciate such a display in that type of somber mood.