Our site allows questions about notable claims on almost any topic. It is therefore unsurprising that we need to have a well specified migration policy.
What are the conditions under which we should migrate questions to other sites?
Example of off-topic questions are questions which are not about a notable claim, or not about a claim at all. Direct questions about a field of science, for example: "How do lightnings work?". We also don't allow research-level questions, for example: "What are the consequences of faster-than-light neutrinos?"
Although it is not required by the software, it is common practice among moderators to ask for permission before transferring a question. It is also useful, because questions might need to be retagged or edited to fit better in their new home.
The migration needs to be proposed to the author by the community or a moderator. This should be done concurrently to a close vote, as it should only be done on off-topic questions. If the author accepts then the question can be migrated to its new home, if the author refuses it will be closed (or stay closed).
Abandoned questions can be migrated without the author's permission.
Sometimes questions are on topic, but possibly better served somewhere else. In this case, it's only appropriate to migrate with the author's consent.