What are the biggest mistakes designers make presenting their work?

I think designers are apt to make the same mistake many professionals in any field of expertise make while in the thick of presenting work: operating out the gate with a blindspot for their intended audience. By that I mean designers can be obtusely unaware of the clarity of their solutions; what we see in our own heads isn't always what is perceived by its eventual audience, and much time can be wasted in the process of explaining.

The best designers clearly communicate solutions with an almost "well, duh!" simplicity, an acute empathetic motivation to clarify complexity into digestible "ah-ha!" moments for anyone.

How does that influence how you write about it?

Well, it definitely makes my work more difficult as a writer, especially when navigating an overabundance of marketable or industry catchphrases in hopes of promoting interest. Of course, it's my job to dissect and disseminate, but if a pitch seems overly complex, poorly communicated, or incomplete, I'm more apt to pass on reporting about it. I have a great curiosity about concepts, but an even greater appreciation for realized solutions, recognizing as a former art director and industrial designer the difficulty of turning an idea into an executable and successful design. Ideation without a clear explanation is like pasta without sauce.

Is there a simple trick to avoid those mistakes?

The simplest trick is to continually present to those outside the industry and attempt to do it in the most succinct and simple manner. Filter, edit, simplify. Present your design to your grandparents, your little brother, a co-worker in a different department, or anyone else who offers a fresh pair of eyes, ignorant of your design's intent. If you can hook them, you'll most likely hook my interest too.