I've moaned and whined about 'book three' over various boards and several years.
I've deleted it and started over from scratch twice and done major edits (>50% changes) more often than that.
It's the third of a trilogy and must tie up all the loose ends, not that there's many, just that the first two books raised issues that needed to be explored outside of those two stories. I know the final line (a variation of the first line of the first book) and that hasn't changed or felt wrong. I know the characters and the arcs they need to follow. The secondary characters seem to have resolved themselves into useful, believeable beings with properly secondary plotlines.
The story itches in my head and pleads to be written down in those great chunks of 'ignoring the kid and housework' inspiration.
But I'm not starting. I can get as far as formatting the document and setting the title page, header and footer, notebooks full of notes and scene sketches by my keyboard.
Then ..... I play gemcraft, or check domebo for that one new thread or three new replies, or read someone else's book.
I know it's the frustration of having done the bad drafts, trying to force the characters into plots that don't fit them, or making two dimensional bit players just to move the plot ahead. I know it's just fear of yet more wasted effort. The first two were easy, well, hard work and time consuming, but once written, the plots haven't changed significantly, reading them over still sucks me into their stories when I should be checking the grammar. This one, I read it and hate everything (except for a couple of scenes which will survive V2.4 because they are freaking perfect). I suspect there's a little fear of finishing, that the trilogy can't be rejected if it's bever finished, but that hasn't stopped me sending out the first part to collect rejection slips all by itself.
Give me hints, give me inspiration, give me stories of your own stalled masterworks.
Help.