Why did the Ohio nuke plant employ Mohammod Abdulazeez for any length of time? (UPDATED)

UPDATE 11:10 PM EDT July 18
A Fox report today throws more light on the answer I sought than the July 17 ABC one (below):

Fox8 reported that after being hired to work at the nuclear reactor, Abdulazeez went through orientation while he waited to be cleared for permanent employment.

A plant spokeswoman [at Perry Nuclear Plant], Stephanie Walton, told the station that his employment lasted all of 10 days, from May 20 to May 30. She said Abdulazeez was fired when he “did not meet minimum requirements for ongoing employment.”

The Associated Press reported Saturday that a federal official briefed on the matter said the issue was a drug test. Perry had earlier said that Abdulazeez had failed a background check.

The Fox report also mentions that the perp was hired by the plant as an engineer and that he "worked as an intern a few years ago at the Tennessee Valley Authority, the federally owned utility that operates power plants and dams across the South."

As to why ABC News couldn't have procured this same information -- too busy, from their report, trying present Abdulazeez in a sympathetic light and psychoanalyze him.   

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From ABC News report, Chattanooga Shooting Suspect Briefly Worked at Nuclear Power Plant

Jul 17, 2015, 6:03 PM EDT

Abdulazeez, who graduated from the University of Tennessee Chattanooga with an engineering degree in 2012, worked at the plant in late May 2013.

Todd Schneider, a spokesman for FirstEnergy, which runs the plant, told ABC News that he "was never granted unescorted access and never entered the secured area of the plant."

Abdulazeez's employment did not extend beyond 10 days because "it was determined that he did not meet minimum requirements for ongoing employment," Schneider said.

"During his brief conditional employment, Abdulazeez’s access was limited to an administrative office building while he received general training on company procedures," Schneider said. "He did not have access to any sensitive plant information."

I don't get it; I don't understand why they couldn't have determined during the interview and testing processes that he didn't have the qualifications for the job. I mean, this isn't a job at Starbucks we're talking about.  

And I've never heard of a conditional employment period that only lasts 10 days.  So what was Schneider saying? That his job performance was so awful they had to fire him after little more than a week?    

Schneider doesn't mention the position Abdulazeez was "conditionally" hired for, and it seems ABC News didn't ask.  

Instead the ABC reporters filing the story -- all five of them -- chatter on and on about what a nice kid Abdulazeez was and how nobody could believe he would shoot people in cold blood. 

How many American investigative reporters does it take to change a light bulb these days?   

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