[rozenmd]

I built a website monitoring service (last I checked, 191 alternatives on AlternativeTo).

Customers really really really don't want to have to run their own solution. They want to be able to pay someone to make the pain go away.

(https://onlineornot.com if you're curious)

[TAForObvReasons]

I personally feel that uptime monitoring, status pages and similar solutions should always involve a third party. You can run your own service, but you would have to trust your service to be working properly. And in the exact cases where uptime monitoring is relevant, you may end up facing issues with your own monitoring service.