Safe is not locked. To be safe is to be locked. Unlocked. Unsafe.
The possibilities for action change, based on whether the actor is entering a scene or exiting a scene. Or, god forbid, they are hanging around in the background in the chorus. What do you do with that? But think about the motivations of characters entering: they are all possibility and potential. They hold the cards in their hand and choose which ones to lay out. The character exiting has all the cards out on the table and their hand has been read. The story has been told and perhaps there is possibility and potential there as well, but it’s found behind a dark curtain and isn’t clear yet. Both have either everything to lose or nothing to lose.
In improv, scenes are pushed forward by heightening the stakes and by the characters heightening and changing their status toward each other. You can watch a scene play out one way and then imagine what it would be like if you switched the roles or changed the status of the characters. Would they react the same way to each other? Is there something inherent in the character that would remain even as all the elements around them are altered?
Evidence. Left behind, hidden, discovered. Evidence of impact made.