For me it's two things:
- In a dream I seem to have some ability to force myself to "wake up" if I really want to. I haven't seriously believed I could do that when I'm awake, but who knows - maybe being awake is just a much more convincing dream.
- Sometimes when I'm dreaming there are weird enough things happening that I do suspect that I'm dreaming.
Advertisers need to see more articles like this. Pulling the ad dollars away from Twitter is the last lever anyone has to try to change it, and it should have happened long ago at this point.