A: Nothing is ever deleted. Organizing only moves objects between collections and creates new ones — your objects, meshes, materials, modifiers and existing collections are never removed.

Every run is reversible three ways:

• Revert restores the previous layout exactly, touching only the objects that actually moved. It works up to 20 runs deep in a session.
• Ctrl+Z works normally.
• Organize a single collection instead of the whole scene (right-click it in the Outliner) and the rest of your scene is untouched.

In AI mode, if the request fails for any reason — no connection, expired session, usage limit — your scene is left exactly as it was and you get a message explaining why. It never silently reorganizes things a different way. Names the AI doesn't classify stay right where they are rather than being dumped into a catch-all. And re-running on an already-organized scene is safe: the result is idempotent, so the layout doesn't drift.