This is an interesting representation from the investor perspective by Jason Lemkin why he does (not) want to fund you. Some are relevant to presentations (my words):

• Integrity: gaming metrics, locker room jokes
• Exit strategy slide shows that you are not committed (not sure all investors will agree)
• Pooh-poohing competition (better to show that you understand them, rather than hiding their existence)
• Looooong industry background sections before getting to the point, the first decision point at minute 5, if you survived that one, the second one comes in at minute 20 
• Document formats that are hard to open

Image via WikiPedia