[@Darcs] I can't remember any he dropped - some are dormant though for sure or their conclusion is alluded to.

The series, though, have dropped so many of my favourite plotlines or just flat out changed then into simpler, less interesting scenarios. (Sansa, for example).

[@Aeonumbra]George R R Martin.

[@TheMadAsshatter] My wife has a similar issue, she did a Creative Writing degree and is published in a few poetry collections but a novel is her real aim, she just finds it hard to keep it going without wanting to go back and edit or drastically change something.