This is the reverse view–the back office, as they say on Wall Street. It Why are back doors always more interesting than front doors? Stage doors more than grand lobbies.
If there was a door in the Roman Colisseum marked LIONS ONLY, it probably had a certain allure, less so if you were the one booted in to meet your sharp-clawed destroyer, who was a bit miffed at having not been fed since he devoured his last bony gladiator a week ago Tuesday.