When I reimport my project's Library, I get lots of warnings such as

State combat.Ghoul Attack has no motion

but I have no idea why. In this specific case, I looked up Ghoul Attack. Here's the state in which it appears, in the only animator controller that includes anything called Ghoul Attack:

State:
m_ObjectHideFlags: 3
m_PrefabParentObject: {fileID: 0}
m_PrefabInternal: {fileID: 0}
m_Name: Ghoul Attack
m_Speed: 1
m_CycleOffset: 0
m_Motions:
- {fileID: 7400000, guid: 0db269712a91fd641b6dd5e0e4c6d507, type: 3}
- {fileID: 0}
m_ParentStateMachine: {fileID: 110708233}
m_Position: {x: 492, y: 132, z: 0}
m_IKOnFeet: 1
m_Mirror: 0
m_Tag: 

I thought perhaps that second one - {fileID: 0} was throwing up the warning incorrectly, so I removed it. There was no effect, I still get warnings about Ghoul Attack. So given that the only state I know of with that name does in fact have motion, what is this warning actually trying to tell me?