I bet that's it. And/or, "hey the sales are falling! Better hide that bad news" Both are bad ideas, blinding them just when they need the data.

I'd rather risk having my competitors occasionally get some of my data, than risk not sharing data freely within my own team.

The competition is likely already getting those signals anyway, and the larger your organization, the more likely that you've got many internal blind spots that you really need to address.