The director had to believe that was the best take worth using, or even make the decision to stop doing takes because they had apparently made one that was good enough.
Speaking with French publication Allocine, and translated by ComicBook, Marion Cotillard does bring up one point that’s worth considering.
The scene was edited into the film in the way that was by somebody else.
It may truly be a terrible death scene, but it was a team effort that made it bad.