Ex-Windows chief Steven Sinofsky is “happy” with the miserable sales record of tablets and PCs running his Windows 8 baby.

Speaking at the Wall St Journal’s D11 conference yesterday, Sinofsky pitched sales of Windows 8 licences as something to be proud of, saying the jury’s out on who will win - Apple, Android/Samsung... Microsoft?

In a rather safe Q&A session with D11 hosts Walt Mossberg and Kara Swisher, Sinofsky said: “It's hard for me to look at selling 100 million of something and not be happy.”

His former employer earlier this month claimed it had sold 100 million Windows 8 licences.

As The Reg wrote when Microsoft started touting that 100 million number, and as various analysts’ numbers have proved, there is absolutely no correlation between licences sold and devices actually in the hands of users.

These numbers are a prop Microsoft has used to prove success. It is nothing more than an insider baseball metric that means little in the real world.

Licences are sold to the IT channel and volume customers, but it’s up to the channel partners to sell the machines of the volume customers to activate their licences.

Look at the Gartner and IDC numbers, for example. The analysts both recorded a massive drop in worldwide PC shipments - and hence orders - for the first three months of 2013, just after Windows 8 launched. IDC said shipments had fallen 13.9 per cent to 76.3 million units – twice as bad as it had initially expected. Gartner reported an 11.2 per cent drop with 79.2 million units.

As for Windows-8-powered slabs: IDC says just 900,000 Surface RT devices – running ARM - and Surface Pros, using Intel, shipped in the first three months. This gave Redmond a 1.8 per cent share of the market of 49.2 million devices sold globally. Apple led global sales with 19.5 million iPads sold.

100 million licences... but what does that MEAN?

If you do want to take Microsoft's number at face value, it’s worth adding some context. As Microsoft blogger Paul Thurrot pointed out at the time, the average monthly licence sales dropped by three million during the second-half of the six-month time frame which Microsoft used to calculate that number. Also, while the 100 million matches sales for the earlier Windows 7, the addressable market for Windows 8 was supposed to be a far larger.

When Sinofsky was asked why Windows 8 sales haven’t revived PC sales, the ex-Windows chief took refuge in the future. “It will take a long time for things to play out,” he said. “It’s exciting, but it means while it’s going on you have to resist the urge to pick winners and losers.”

It’s the kind of history-will-prove-us-right, hard-to-benchmark argument right-wing US hawks used to justify the Iraq invasion.

For the sake of history, let's remember Windows 8 hasn't just not helped revive sales of PCs - it has actually hurt them. Bob O'Donnell, IDC's program vice president for clients and display, wrote at the time of his company's predicted PC sales numbers: "It seems clear that the Windows 8 launch not only failed to provide a positive boost to the PC market, but appears to have slowed the market."

He blamed the radical changes Microsoft had made to its UI with Metro, the removal of the familiar Start button, and the relative expense of touch PCs.

Microsoft is now in retreat on Windows 8 after a backlash from users who were pained at being denied the familiar PC desktop and flung into the touchy Metro UI. “Key aspects” of Windows 8 are being changed, with at least the return of some kind of Start button in Windows 8.1. It’s not yet clear whether a Start menu and the ability to boot into the classic desktop without Metro will be included.

Sinofsky left Microsoft unexpectedly and amid much mystery just three weeks after the launch of Windows 8 and before the 2013 launch of Surface Pro tablet. He is now an “executive in residence” at Harvard Business School, where he writes about “disruption” and “conversations” on his blog Learning by shipping.

At D11 we finally heard the question that counted: Why’d he go so suddenly? According to the All Things D blog: “You have to pick a time, so I picked a time.”

Yup. You godda go when you godda go. Like midway through the launch of your company's flagship product. ®