When is a "goof" not a goof? When it's Godard!
I was going to write in an mention a tracking shot where the girl meets up with her lover at an airport hotel as a "goof". During the tracking show, we twice see the camera operator tracking along with the girl sitting in a wheelchair. The wheelchair is reflected quite clearly and obviously in some two sections of a wall.
But, being Godard, he probably just left it in, and almost hoping that eagle-eyed viewers would see the wheelchair! Plus, being a low-budget film, there obviously weren't going to be re-takes.
But, I prefer to believe that Godard would enjoy the idea of viewers seeing the 'magic' of movie-making being winked at!