I believe the technical term is called "
deux ex machina." The classic version of this of course being "s/he woke up and it was all a dream."
Unfortunately, some writers are simply not creative enough to come up with a good ending. Or, as I have sometimes put it: Fully half of all Americans believe they have at least one book "in them." Unfortunately, in many cases, that's exactly where it should stay.
Eric (Yet another wannabe, so I shouldn't talk, though I do earn my living as a writer, albeit mostly in advertising and for various websites).