[Twisted-Python] SURVEY: Have you submitted a patch to Twisted and it never got in?

In order to have at least some anecdotal evidence -- If you've submitted a patch to Twisted (or started a branch) and it never made it in, how did that happen? I imagine reasons might include a review request to write tests, redesign requests, getting distracted, "it works for me", design discussions that never got anywhere... What happened in your case? (I'd also like someone -- lvh? -- to go through report 16 and see if we can come up with a summary of how those tickets ended up where they are.)