Ambient tropes we're all guilty of but love anyway:

Rain
Birds/water/wind field recordings
Shortwave radio / Numbers Stations
Film samples (esp Blade Runner)
Yamaha CS-80 leads
Japanese train station announcements
Ticking clocks
Fear of Major Keys
No tracks under 10 minutes

At least 1 track in your discography called 'Home'
Not a single press photo of you smiling
Bio that makes you sound like a pretentious twat
All the budget spent on excessive packaging
"I hope to release it on vinyl someday"
Limited to 100 copies

Obsession with dystopia
At least one LP about outer space
80 minute album consisting of one single track
The obligatory ambient techno album in discography
Permanently poor because all profit is spent on new gear
Currently making an album with the theme of isolation

Album concept more interesting than the actual music
Obscure 80's Japanese ambient LP reissued on vinyl
"Soundtrack for a film that doesn't exist"
Artist almost died at one point in their life
Weekly Twitter rant about Spotify and/or Capitalism