The head of the Windows division at Microsoft has left the company after 23 years of service, just days after the worldwide launch of Windows 8 and the Surface tablets. 

Steven Sinofsky, whose final task appears to have been leading the team developing Windows 8, is to be replaced by fellow Windows exec Julie Larson-Green.

Microsoft has not explained reasons for Sinofsky's departure, though the move comes while the company has chosen to not disclose the sales figures for its Surface tablet other than to say they are "modest".

Meanwhile, in the year leading up to the launch of Windows 8 there has been a vehement debate on whether it is a step forwards for the entertainment industries.

Respected games executive Gabe Newell branded the machine "a catastrophe while Minecraft creator Markus Persson said the new OS could "ruin the PC as an open platform".

In an email statement sent to employees, Microsoft chief executive Steve Ballmer said the company has "delivered the foundation for a new era for Microsoft".

"From Office to Bing to Windows Phone and Windows Azure, to Xbox and of course Windows and Surface and everything in between, we've unleashed a huge wave of devices and services that people and businesses love," read his statement, which was published on Venture Beat.

"We are facing a time of great opportunity. What we have accomplished over the past few years is nothing short of amazing, and I know we have more amazing in us. I am excited about our people, I am energised by our ability to change and grow, and I look forward to the success which lies ahead."

http://www.computerandvideogames.com/378232/windows-8-chief-quits-microsoft/

Do people quit their jobs only if there is trouble? 

why would he stay ? he finished his job and released his product.

Hasn't the bolded already been called out as fail?

More details behind Sinofsky's departure here: http://allthingsd.com/20121113/in-the-sinofsky-departure-bill-gates-sided-with-the-other-steve-ballmer-at-microsoft/

The parallels to Scott Forstall really are striking.

Hmm, good business guy but not enough of a public figure really, not a really big deal.

The article seems to make an attempt to associate him leaving with "modest" surface sales.

Maybe he was sacked. Maybe as someone suggested he finished what he was employed to do and moved on.
It is not clear from that article why he is no longer at MS.

So unless you have more info from another source both are just assumptions and not yet confirmed fact.

When asked about Surface, Steve's use of the term "modest" was in relation to the company's approach in ramping up supply and distribution of Surface with Windows RT, which has only been available via our online store and certain Microsoft retail stores in the U.S. While our approach has been modest, Steve notes the reception to the device has been "fantastic" which is why he also stated that "soon, it will be available in more countries and in more stores."

After being there for 23 years, I'd say yes.  It didn't say he retired...

I will let time be the judge of it's success rather than Balmer. I hope it does well, though.