Whew! See how many parts there are to an ending? And we're not even done yet!
The following component is specific to romance novels, so if you're writing something else, it might not apply to you.
The Declaration of Love. This is kind of like the mini-climax in romance novels (heheh, that sounds like a bad pun). It is crucial for the success of the hero/heroine's relationship that they both confess their feelings to each other.
- Do they say it on "Goldilocks Time" (not too early, not to late)?
- Has this moment been built up to throughout the course of the novel?
- Do both the h/h actually verbalize their feelings?
- Does how they verbalize their feelings fit their characters (aka: someone who's been rough and ready throughout the book isn't going to suddenly write a Shakespearean sonnet at the end- unless you've already shown they are really the type of person to write Shakespearean sonnets. But that's another matter.)?
- Is this moment sufficiently acknowledged as a milestone (no, "I love you. How 'bout those Knicks?")?