A false ending has two contexts; in literature it is a narrative device where the plot seems to be heading to its conclusion, but in reality, there's still more to the story. In a musical composition, it is a complete stop of the song for one or more seconds before continuing.
The presence of a false ending can be anticipated through a number of ways. The medium itself might betray that it isn't the true ending (i.e. it's only halfway into a book or a song, a film's listed running time hasn't fully elapsed, only half the world has been explored in a video game, etc.), making only stories with indeterminate running length or a multi-story structure able to pull this off effectively. Another indicator is the feeling that too much of the story is incomplete when the false ending comes, making it feel like there has to be more.