Generally speaking, a mediocre movie is one which isn't inherently bad but just doesn't quite pass the threshold of good either.
Whether falling short of expectations or simply being acceptably watchable, these films are all fine examples of cinema that lingers in the middle-ground quality-wise - not awful, but also lacking an effective creative spark.
But each of these 10 films also features a single brilliant scene, whether a stunning action sequence or an incredible sliver of dramatic acting, which suggested the filmmakers were all capable of so, so much more.
In some cases these scenes stick out like a sore thumb compared to the rest of the film, while in others they occur early enough to false set the audience's expectations for the two hours to follow.
Either way, these scenes don't generally get the credit they deserve, entombed as they are within hit-and-miss movies that can't match this excellence throughout.
As isolated sequences they're expertly crafted and a delight to watch, but will doubtless leave you wishing they were surrounded by stronger films overall.
Instead, they live on as indelible quasi-short films while the larger movie has in many cases been dismissed or even forgotten by the mainstream...
10. Quicksilver Evacuates The X-Mansion - X-Men: Apocalypse
X-Men: Apocalypse turned out to be one of the most disappointing films in Fox's X-Men franchise, delivering a bloated, strangely generic follow-up to the brilliant Days of Future Past that failed to make the most of iconic villain Apocalypse (or Oscar Isaac in the role).
But Apocalypse features a single grandstanding scene which makes sitting through the 144-minute slog of a movie worth it - Quicksilver's (Evan Peters) delirious evacuation of the X-Mansion.
Trying to match or even top Days of Future Past's unforgettable slow-motion Quicksilver scene was a thankless task, but this scene impressively got pretty damn close.
Set to Eurythmics' "Sweet Dreams (Are Made of This)," Quickie speeds through the X-Mansion, frantically evacuating the students after Apocalypse detonates an explosion in the building.
Between the creativity of the various ways Quicksilver saves the kids, the hilarity of him stopping to rescue animals - including a pizza-loving pug! - and the sequence's stunning visual design, it remains one of the greatest scenes in the entire X-Men franchise.