>If it was good at predicting crime I highly doubt only 2/38 departments would have cooperated.

That's certainly low, but I suspect (absent some legal framework like FOIA) the default position of police departments is to share less information, not more. So it's still what I would expect even if it was reasonably good.

I wish the article would have provided more details about why the PDs chose not to use it. Was it because it was bad at predictions? Cumbersome to use? Glitchy?

It reminds me of a project I was involved with that used a "real-time" computational fluid dynamics model to optimize datacenter air-conditioning. Management was big on the hype, but if you paid attention, the system was routinely unplugged from the actual control system because the facility engineers just found it too difficult to work with.