Here are some common mistakes I see in briefings for presentation design projects. They range from typographical details to big picture issues:

• The presentation never explains what it is you actually do
• The slides say something different than the verbal explanation
• Too many benefits, as a result: no positioning
• Doubt between positioning options shines through in the slides
• Presenter gets lost in side stories
• Amateurish images ("funny" ones)
• Images with copy right issues
• Font, colour, alignment, image resolution, aspect ratio chaos
• Inconsistent graphical style
• Inconsistent analogies
• Cliche analogies
• Good data, but the wrong data charts
• Jargon and buzzwords
• Quotes from airport best seller authors
• Bullet point place holders rather than a story
• Too many words that explain too little
• Too few words that say something generic
• Five slides combined in one
• The presentation spends too much time on the obvious
• The presentation avoids the elephant in the room
• Slides from a strategic Board meeting that talk about some strategic choice and expose weaknesses are ported straight into the pitch deck
• Comments and notes with sensitive information are left in presentations for everyone to read
• Sensitive data that is taken out of the chart can still be accessed when opening the graph
• 99% solution, 1% problem
• About us, us, us, us
• Too long a summary, too short a body, too long a wrap up
• Errors marked by the spell checker are still ignored
• Custom fonts that get rendered as Arial
• Slide title appears 3x: in the title, in a bubble, in a line across the bottom
• Second line of a bullet point paragraph is misaligned
• First line of a regular non-bullet point paragraph pops out as if it were a bullet point
• Inconsistent slide templates throughout the presentation (resulting from a Frankenstein, slam the deck together, effort)
• Some charts are still in Microsoft Graph / Microsoft Office 2003 format
• Data charts are copied straight from Excel, without bothering to round up/down

Art: Giovanni Boldini (1842–1931), The Laundry, 1874