Software giant's history in the mobile division was "clearly a mistake".

Microsoft co-founder Bill Gates has emphasized that he's "not satisfied" with the software giant's innovations, especially in the smartphone market.

During an interview with "CBS This Morning," the Microsoft chairman was asked whether he was happy with Steve Ballmer's performance as the company's CEO. Although he stated that "many amazing things" have come to fruition under Ballmer's leadership over the last couple of years, Gates stressed that he's not satisfied with the firm's innovations.

"Well, he and I are two of the most self-critical people ... you can imagine," said Gates. "And here were a lot of amazing things that Steve's leadership got done with the company in the last year. Windows 8 is key to the future, the Surface computer. Bing, people are seeing as a better search product, Xbox."

"But is ... is it enough?" he added. "No, he and I are not satisfied that in terms of, you know, breakthrough things, that we're doing everything possible."

Gates pointed towards Microsoft's position in the smartphone sector as an example of the company's shortcomings. It currently accounts for 2.4 percent of the market with its Windows Phone platform.

"There's a lot of things like cell phones where we didn't get out in the lead very early. We didn't miss cell phones, but the way we went about it didn't allow us to get the leadership. So it's clearly a mistake."

Gates' comments were made during an interview pertaining to the Melinda and Bill Gates Foundation, where he has donated a substantial amount of money for philanthropy since stepping down as Microsoft's CEO in 2008. During December 2012, he had a net worth of $65 billion, which is after donating more than $28 billion towards numerous charitable causes.