All of the flaws you see in Microsoft today are as a result of their own intrusions into user privacy. If they never intruded privacy, and instead focused on providing a secure operating system for their consumers, Windows would not be near as vulnerable as it is today.
Look at the cause. Microsoft is a company, and a company always tries to maximize profit. There is no doubt that privacy intrusion, as long as it's not against the law, is profitable. And not just profitable, but the single most important asset of current Internet companies. If consumers don't care about that, don't expect Microsoft to blame their ethics. They're going to take advantage of it.
Now as for security, it doesn't have to do much with focus, but with another fundamental problem that is inherited in closed-source software, which is smaller group of code auditors.