Many youtube videos are merely clickbaits, and some of them will have these red arrows or red circles, pointing to the "amazing detail in question", on the video thumbnail. Red circles and red arrows are my own personal "clickbait alert"
Other clickbait alerts are thumbnails focusing on boobs (duh), as well as obvious (maybe not to everyone though) photoshops, for example "dangerous animals compilation" showing a shark throwing a giraffe into the air, or whatever
On that subject, I hate hate hate hate hate TomoNews, they'll put authentic security cam stills in their thumbnails, but in the actual video they'll *only* show their retarded in-house 3D animations instead. I have granted those fuckers SO many unintentional clicks