I'm fixing some minor things on the 404 page for all my websites. My punctiliousness makes me unable to sleep well unless I get an answer to this question. :)
Does a 404 page need a meta description tag? If yes filled with what, "page not found"?
I would say no, if Google really cares more about contents and user frienly site rather than about what is on the page (moreover the 404 page snippet should never show up in Google cause server is sending real 404 code).
But after reading all this stuff:
on how they suggest to fill up a 404 page (that I always thought should just be a simple 404 page) I started to feel worried about meta description too.