Why Speakers Suck, a follow-on to Reid Hoffman's post about panels

In 10+ years of going to conferences I've seen exactly three truly great presentations (which a measure by whether or not I can still remember them, their core fact, and if they impacted my work or my own presentations in any way). One by Netflix's Casey Rosenthal, one by Hashicorp's tandem of Mitchell Hashimoto & Armon Dadgar, and one by Erlang Solutions' Iñaki Garay.

I've seen a lot of presentations over the years, and some of been good, but have been ultimately forgettable over time. Most have failed the simplest litmus test I use... does it seem like the speaker would want to sit through their own presentation? Because usually it seems like they want the audience to sit through something they themselves wouldn't want to wade through if they were in their own audience.