I think he means uncirculated as in backdoor cards. 2005 Fleer Series 2 BB id an example. They were officially released, so uncirculated, that some found their way into hobby circles. For that set, we have a running checklist as they are found.
To answer the question, pretty much same as any other card. Depends on the player, the perceived scarity of the release and such.
When the sky is coming down
When you feel like you're going to drown
When you know the end is all that you've been looking for
When the pain is too much to bear
When there's no one who will care