An excellent post on the "Tekst en Communicatie" blog by communication expert Louise Cornelis. It's in Dutch, so I will translate.
Louise discusses what she refers to as "the big f*cking arrow" or "BFA" (not all Dutch on her blog). A huge arrow in the middle of the slide, pointing at a block of text with the chart's conclusion. Apparently "BFA" has become a well-known acronym among chart designers in The Netherlands.
Her (and my) recommendation: get rid of it and stick to a clear title headline.
SlideMagic: a platform for magical presentations. Free student plan available.