Re: Rock, meet Hard Place
I know testing feels like a good idea, but honestly, how much worthwhile testing can your organization do over and above that done already by the manufacturer? And, if you don't trust them, why the hell are you using their products?
Pretty much every organisation will do some SAP customisation which will require testing.
Also, some companies run in a regulated environment where every patch, code change, OS update needs to be validated. At my work a lot of the factories manufacturing medicines etc. have SAP on the backend; you really, really don't want system changes to screw that up!
Biting the hand that feeds IT
