It's the kind of error an operator could makes as a wrong choice on a menu or the entry of the name of the last network worked on instead of the one needed. In short, it was a human error that's all too likely to occur with anyone momentarily preoccupied with the price of mangoes or a flare up with a spouse.
The public perception of computer systems is that they are mindless robots who interpret commands from operators literally and then follow through with them relentlessly, even when the operator realizes he made a mistake. There is actually a lot of truth to that perception. Regarding human error when inputing parameters or choosing menu options for a critical operational process, this can easily happen when the process is performed manually using a tool like SSMS or through a command prompt.
However, there are ways to make the process more intelligent and fool resitant (not necessarily fool proof). For example if the operator clicks on a server group and chooses an option to start deploying a service pack, the process should query a table to determine if that service pack has already been applied to each server and when. If the query determines a duplicate or invalid set of parameters, then the process should then prompt the operator for comfirmation or even block the process from starting until an override is given.
"Do not seek to follow in the footsteps of the wise. Instead, seek what they sought." - Matsuo Basho