I was wondering about this the other day, and had a quick look into it. I was wondering if we could do something clever, like use a StackApps script to automatically migrate questions across. (I'm sure similar ideas have come up on other SE boards in the past... )
However, there are a few side-effects to migration that would have an effect on the both the user who posted the question and anyone who had already answered it. We'd potentially be affecting the reputation scores of people on other boards.
For example, in this post on the main StackOverflow Meta board:
Down votes are cleared from the question upon its migration
If a user who has participated in the question does not have an account on the target site, their username is displayed as plain text
until they create an account
Answers on the origin site are deleted immediately upon question migration (This causes a reversal of all associated reputation on the
The question is left as a stub, or pathway to the new site, for 30 days, after which it is automatically deleted (Again, this causes a reversal of all associated reputation on the origin site.)
There are also other considerations (again from the linked post)
Don't migrate crap! Ever. If the question is likely to be closed or deleted on the destination site anyway, don't bother migrating it.
Just vote to close it normally and advise the OP of the other site in
the comments. If they decide to improve the question, then they can go
post it over there, or they can edit their question so it's on-topic
on the original site.
Check for cross-posts. It may be possible, that after hearing about the other site, that the OP may cross-post their question onto
the other site. Therefore, check the intended destination site for
potential cross-posts before voting to migrate. If it has been
cross-posted, vote to close it instead, as cross-posting is prohibited
even if the question is on-topic on both sites.
Avoid migrating answered questions. The point of migration is to send the question to a place where it is on-topic and can get
answered. If the OP already has an answer, then we've already defeated
the purpose of migration and the destination site won't have anything
to do with the question. Avoid migrating these questions unless they
are of extremely good quality and risk deletion on their current site.
Don't migrate for the sake of migration. We only migrate questions because they are off-topic on the original site. It is
perfectly possible for a question to be on-topic on multiple sites,
but that is not a reason to migrate it elsewhere, unless the OP
requests migration. As a general rule, if someone asks a question
here, and it's on-topic here, it should stay here.
Be familiar with the destination site. If you have never even visited the destination site before, read through its about page and
help center thoroughly and make sure the question actually belongs
there. Don't just look at the name of a site and automatically assume
that the question can be asked there. Each site has its own rules, and
rules vary greatly across sites.
If you're not sure, don't vote to migrate it. Let someone else who is sure do that, or ask for opinions from the community in a
relevant chat room.
I'm not saying we shouldn't be more proactive about migrating, it's just that it might be slightly more complex than first thought.