Unacceptable Goofs - Vague Explanation

In the following section: https://help.imdb.com/article/contribution/titles/goofs/GFDUF27RBTQGS8UZ?ref_=helpms_helpart_inline# Concerning the "B. Unacceptable Goofs", bullet: Unlikely situations: If something is "highly unlikely" or "completely unbelievable", don't submit it. It seems that most goofs can fall under this category. It should be explained further with a few examples.