TL;DR: Don't migrate crap. Use the "other" reason if none of the ones we have applies. If you're doing that all the time with the same basic comment post it on Meta and we'll bug the community team to give us a 4th bucket to throw shit in.
Server Fault currently has 3 custom close reasons -- my two cents on their applicability:
Questions must demonstrate a minimal understanding of the problem being solved.
Generally intended for use when the OP is so clueless as to be unable to help us help them. "How do I set up Apache?", "What is a router?", "How is server formed?" and the like.
A lot of crappy questions fall into this bucket -- we could clarify the wording on this a bit.
(This is a close cousin of the standard
Unclear what you're asking reason -- if it's not obvious the OP is clueless the standard reason should probably be used in preference to this one. I could even get behind retiring this reason in favor of something else and using "Unclear what you're asking" as the general clueless close reason.)
Questions seeking product, service, or learning material recommendations are off-topic
Self-Explanatory: "Which X should I buy?" isn't something we want to answer.
("What tools can I use to accomplish
some well-defined goal" questions may or may not fall into this bucket. Certainly the ones that can be answered with a simple Google search don't belong here, but ones that require a creative combination of tools may escape the axe. There's some gray area for what is/isn't "shopping".)
Questions must be relevant to professional system administration.
For questions which, well, aren't relevant to professional system administration. ("My home media server shit itself. HALP!", "Excel won't open this document. HALP!", and other end-user technical support questions. Also "I'm a developer, how do I set up LAMP?" and the like where someone needs a professional sysadmin.)
Other (Leave a comment)
This is an underused close reason -- If a question sucks so much it needs to die but none of the reasons above fit, make up your own.
If you guys are making up the same reason all the time throw up a meta post and we can ask the community team for an additional (4th) close reason -- I'm sure the ones we have aren't adequate even after the work that went into them to date,