"Gameplay Footage" of a gameplay preview is entirely scripted.
The PR rep presenting the game uses any meme whatsoever.
The PR rep presenting the game compares their game to "another thing, but better" or any equivalent.
The PR rep sucks at their own game.
The PR rep dodges a question or refuses to answer one.
A game gets announced at E3 that's already been announced.
Bethesda doesn't announce an Elder Scrolls game.
EA announces The Sims literally any game DLC.
Valve shows up at all.