Like Steve Jobs, Mark Zuckerberg is someone who cares deeply about creating perfect products, and he pays close attention to detail.

Early employee Noah Kagan, who now runs SumoMe, worked for Facebook for nine months in 2005. He remembers some startling ways the young CEO reacted when he didn't feel an employee's work was good enough.

One time, Kagan recalls Zuckerberg dumping water on an engineer's computer and calling the product he demoed "shit."

From Kagan's e-book about working at Facebook: 

While I don't remember the feature we were working on, engineer Chris Putnam and I had spent almost a month building something we thought Mark would love. He walks to Chris' computer and we demo the product to Mark. Mark thought it was shit. I know so because instead of giving product feedback, he screamed "this is shit--redo it!" threw water on Chris' computer, and walked away. All of us stood around in shock.

In other instances, Kagan says, Zuckerberg had a samurai sword he would fake-threaten employees with when they produced bad work.

He'd walk around with a samurai sword fake threatening to attack you for bad work. Where the hell he got that samurai sword, who the hell knows? Luckily, no employees were harmed while I was there. He'd come around and pretend to cut you joking if you take down the site he'll chop your head off. You have to remember you have a 23-year old uber nerd running one of the fastest growing sites on the web. As mature as he could be he also was still immature.

...He had some great motivational lines. With love, he'd say "If you don't get that done sooner, I will punch you in the face," or "I will chop you with this huge sword," while holding a huge sword in hand.

--This story first appeared on Business Insider.