When you were a demon, a place outside of time-space was not allowed exist for the same reason a mix between a dragon and a unicorn were not allowed to exist. Time-space was already a struggling concept. Yes, experiments found certain relationships but that was only because He was having a laugh. Or whatever. Crowley understood God's attentions as much as the appeal of gossip or the new 300 page strong manual of his new TV.
Crowley's brain failed to come up with any good explanation himself and his level of annoyance steadily rose. He also lacked a decent questions so he decided for a less intelligent one. "Who and what are you?" he hissed in a less than human way.