obviousy physically impossible to go onto negative inventory

But it is not impossible to do transactions out of order. If your receiving agent is gone, and no one can relieve an item, but your assembly line needs to physically use it, are you not going to let them use the parts? Are you going to tell them to wait to do their WO completions because the receipts haven’t been done?

In a perfect world, every transaction would be done exactly as it happens in the correct order. In reality that doesn’t happen, and that’s were negative inventory works as place holders for the late transactions to catch up. Not allowing negative transactions just makes everything super dependent on every other piece.

Now if you have constantly negative things, you have BOM problems, or procedure problems. But disallowing negatives will not fix either of those problems.