Interestingly, the reason I originally looked for and started using it was an unapproved "shadow IT" response to an in-house Nagios setup that was configured and managed so badly it had _way_ more downtime than any of the services I'd get shouted about at if customers noticed them down before we did...

(No disrespect to Nagios, I'm sure a competently managed installation is capable of being way better than what I had to put up with.)