Imagine that you have a system full of millions and millions of pellets, and will be destroyed if radioactive pellets are mixed in with the other pellets.
A process is created to validate and monitor the pellets that are added to the pellets in the system.
The floor chief, for some reason, bypasses the process, and dumps millions of un-validated pellets into the system.
The next floor chief is hired, in large part to try to resolve this catastrophic decision, but the old floor-chief's cronies work harder than ever to prevent him from doing so.
One of the radioactive pellets blows a hole in the side of the plant.
The lackies for the old floor chief pipe up, "It happened on the new guy's shift!"
"Yah, but it's the result of the decisions/actions of the old floor chief, as well as his lackies that have been fighting against trying to fix it!"
Knowing this will be hard to argue against with anyone with a pulse and an IQ above 70, "Well, let's just all agree that this isn't an easy situation to place blame. OK?"
That's basically what just happened here.