I could understand terminating a cop who demonstrated he was unable or unwilling to use deadly force when it was truly needed. Failing to protect his own life, that of another officer, or of an innocent bystander or victim because he just couldn't bring himself to pull the trigger would be grounds to terminate an officer.
But from the article it doesn't sound like that was the situation at all. The (now former) officer assessed the situation and determined the man was trying to commit suicide by cop, but wasn't posing an immediate threat.
That the man was "armed" is not the end-all-be-all of making such a determination. But the media sure loves to focus on that don't they? Most of us are visibly "armed" on a regular basis, though we tend to keep our guns holstered rather than having them in our hands. On the flip side, a couple of large men can present a deadly threat to most individuals despite being "unarmed". A single, committed man can present a deadly threat to a large portion of the population even if unarmed.
Not a good day for the WV Police Department involved here.
Charles