Do you think Jobs was too harsh on his employees or do you think he was a necessary evil in order to create the best possible product?

I got a teacher who is just like Jobs, he respect ppl who work hard and do their best, and ppl that can stand up to him too. My only problem is when he is in a bad mood, the guy gets so grumpy no one can stand him, he complains about everything, he is very professional but sometimes his professionalism makes him "fight" his co-workers.
I'm liking the book @khaleelkazi, probably going to add it to my "to read" list