OBJ asset files can open successfully while still losing important data. The unit axis normalization check should look beyond file validity to units, hierarchy, animation, metadata, and external dependencies.
For OBJ asset, keep the unit axis normalization pass focused on authoritative units, axis conversion, and origin and pivot. Make one controlled change at a time and retain enough evidence for another person to repeat the decision.
Normalize units and axes without flattening useful hierarchy, then verify dimensions and orientation after re-import. Apply this unit axis normalization guidance to the actual OBJ asset delivery path.