So, you're one of the test subjects locked away in long-term storage?
Which reminds me, why did Aperture have a vault filled with people in the first place? Were they volunteers? Another one of Cave's crazy schemes? Normal test subjects moved to extended relaxation from their hotel rooms-on-wheels?
EDIT: I don't guess it matters, since GLaDOS killed all of them within a week of their discovery in the Co-Op campaign.
From what I gather, Aperture had the Relaxation Annex built for the same purpose the hotel rooms in the Relaxation Center. Once the Center was complete, they moved the test subjects stored in the Annex to the newer facility. The humans then took all their remaining employees and hid them in the Annex to save them from GLaDOS. Didn't work out so well.