Steve Jobs discussed in TIME magazine

For Jobs, belief in an integrated approach was a matter of righteousness. "We do these things not because we are control freaks," he explained. "We do them because we want to make great products, because we care about the user, and because we like to take responsibility for the entire experience rather than turn out the crap that other people make." He also believed he was doing people a service. "They're busy doing whatever they do best, and they want us to do what we do best. Their lives are crowded; they have other things to do than think about how to integrate their computers and devices."

In a world filled with junky devices, clunky software, inscrutable error messages, and annoying interfaces, Jobs's insistence on an integrated approach led to astonishing products marked by delightful user experiences. Using an Apple product could be as sublime as walking in one of the Zen gardens of Kyoto that Jobs loved, and neither experience was created by worshipping at the altar of openness or by letting a thousand flowers bloom. Sometimes it's nice to be in the hands of a control freak.

All the stuff is written here:
http://stikhin.wordpress.com/2011/10/08/time-magazine-10072011-steve-jobs-commemorative-issue/