To add to Chris's answer, should the question have been cleaned up, I would have also cleaned up the answers as well prior to migration. The rule
Don't migrate crap should extend to answers as well as questions. Although it's likely some suboptimal answers get migrated alongside a good question, the migration of bad answers should be minimized at the point of origin.
However, at this point, the person asking the question has been seen after I posted the comment, had what I considered sufficient time to improve the question, and has not. Because of that, I simply closed the question as off-topic so crap wasn't migrated.
As far as deciding if migration is in order goes:
- Look at the question. Is the question a good one? Is it well written? Does it have what I would consider sufficient detail?
- Check the comments and answers. Are there crap answers? Are there link only answers? Are there any invalid, rude, or unncessary comments? If there are any, clean them up before migration.
- Check the user's status on the potential target site. If they appear to be trying to evade a block, I close as off-topic without migration. Otherwise, I can potentially migrate.
- If I'm not pretty sure the question is a good fit, I can ping the other mods (when I'm not at work, since WebSense blocks chat.stackexchange.com these days, sadly) and confirm with them that the question is now in good shape. However, I'd probably close for off-topic and leave a comment letting the user know what other sites exist and that I'm consulting with the mods on those sites to see if it's good in its present form.
However, when it comes to migration, a few things do bother me (and I've cleaned some up in the past):
- Users that don't understand another community suggesting the poster ask there. Don't! First of all, you don't know what that community accepts. I (or any other mod) might not either, but it's easy for us to check. Second, cross-posting is bad - migration is better.
- Duplicates of good, on-topic questions are a good thing, except for exact, word-for-word copy duplicates. Once in the right place, the question can be closed as a duplicate. Now, there are more indexed search terms that people can use to find answers.
- One community can't be expected to police another community. There are only simple checks that I can do to see if a question belongs. I can check the FAQ of another community, I can check the user's profile, and I can ping their mods. I'm not going to construct lots of searches and and hunt around their Meta for 20 minutes.
TLDR: Don't migrate crap extends to answers and comments as well as questions. Moderators on one site shouldn't be expected to fully police another site, but some basic checks are in order to ensure any migration is appropriate.