I had a situation where their cloud backup product was not backing up data and not issuing alerts when it wasn't working. I gave them full access to logs, etc.

I had a situation where their cloud backup product was not backing up data and not issuing alerts when it wasn't working. I gave them full access to logs, etc. and the support response was basically that they couldn't determine why it wasn't working or alerting, but it it works for them, so I should migrate to their hosted solution. I sometimes think of the potential company-ending cluster-fudge that could have caused, while I stare wide-eyed at the ceiling at night.