Deleted & Alternate Scenes

Do deleted & alternate scenes help or hurt the movie viewing experience? From the most basic examples of DVD & Blu-Ray bonus features to complete alternate cuts of a movie that add in this extra content, like the Rogue Cut for X-Men: Days of Future Past or the R-rated cut of Batman v Superman. While these scenes were originally fun extras, they are slowly becoming almost required viewing.

In our opinion, if a movie's theatrical cut can not stand on its own merit, but instead needs to wait for the extended cut to come out in order to make sense & fill in plot holes that either the director or the studio was too lazy to fix the first time around, that's just a bad movie. If, however, the extended cut is more of a Director's Cut that adds to the original vision, but the theatrical version was still good to begin with, then it is absolutely the director's prerogative to add these new story elements. The problem today seems to be that studios are starting to lose sight of the difference between these two situations (we're looking at you, Warner Bros...).

Question of the day: what has been your favorite alternate or deleted scene from a movie & why?