On: Root cause of failure, root cause of success

Happy families are all alike; every unhappy family is unhappy in its own way.

C functions have one return code for success, and a thousand for the different ways something can go wrong.

You can very clearly root cause a failure. In the reverse case you can identify aspects of the success whose absence would have caused a greater chance of failure, but there are still many more ways for a project to go wrong than there are for it to go right.

[Citation needed] that the way it can go wrong are more and that they are different.

The research community on complex system safety disagree with you here.