[johnnyanmac]

>Why use a closed source tool and take on that risk when great open source ones exist?

in the case of servers: because open source servers literally can't support your scale of business. That's one of the few places where Open Source can never truly succeed: when you need a lot of hardware and the operating costs exceed any income coming in.

By that point it is a lot better to roll your own servers. But that is of course crazy expensive. Even other multibillion dollar corporations choose to leave some server management to places like Amazon/Microsoft.