There is a consistent theme that I often see when I have been invited into conversation(s) regarding Windows 8 and the whole HTML5 saga. The main undercurrent is "Why would they do that?" and it is a perfectly valid question that often gets lost in the whole opinion / news pieces that are floating around.
Understand the metrics first.
Inside Microsoft you are really goaled around a metric that involves the words "market share" in that somewhere along those lines your entire reason for drawing a pay cheque distills down to that. You have to help Microsoft grow its market share across all battlefields and there are multiple battlefields in play.
Battles are what are happening in today's software industry. It is quite competitive and cutthroat in many places and often mercy is for the weak. Companies on both sides often play by the rules governing ethics but often more so than ever it is not the case under the covers or behind closed doors. There are often many tactics at work that the audience(s) and customer(s) do not always see.
For instance, when Silverlight/Expression was heating up in the early days the battle between Adobe and Microsoft was quite intense (I myself was caught up in it quit easily). You'd have situations where Adobe would threaten to shut down a conference if Microsoft Staff showed or you'd have Adobe specifically target Microsoft showcase wins the next year and spend large amounts of $$ to win the customers back to create the perception that these customers had buyer's remorse.
Apple, Google, IBM and Oracle all suffer from the same somewhat software industry driven guerrilla warfare style tactics. It is a competitive sport and staff within get quite emotional and aggressive at times about it - like a thunder dome of super geeks.
Tactical approaches and competitive aggression is what fuels Microsoft often. It has also to answer the question you have around "Why would they do that" simply put; it is about building an army primarily.
Understand the Tactical Programs
You have programs in play like BizSpark - an idea to give the software away for free in order to seed start-ups into adopting the Microsoft technology stack. It is the old heroin addiction formula at work, in that the first hits free but the second and third will cost you. Ensure an addiction takes place then the monetization will follow.
Understand the Compete motions
The thing though is this playbook or this strategy is in no way different to the days when .NET was first created and it is again a rinse/repeat formula being played out.
The motivation is growth around developer share (that is an obvious objective around winning) the other objectives are also around competing head to head with Google & Apple. Google is the main focus though, this company is taking bodies from Microsoft staff lines often and if you were to look at the past two years around who's left the .NET development teams as well as the Internet Explorer teams for Google it's almost alarming.
Google don't need to compete with Microsoft, they just need to re-hire their staff and I often giggle about this as I once wrote an internal memo regarding Adobe compete whereby I said "We should make a $300k a year offer to their entire evangelism staff to work for us, we say here's $300k now go sit in the park and enjoy life for the next 2 years as it would be cheaper than what we spending on compete for Adobe".
Google are kind of doing that in many ways.
Understanding the gullibility.
Google played Microsoft and it is this small random pocket of competitive insights that often go unnoticed in the industry. These small little gems of "hah that was funny" all add up to the situation we see before us today around why Windows 8 looks and is likely to act in the way it is.
There is no real strategy here, just tactical competitive reactions played out that do not often give pause to the massive impacts it places on the hordes of developers who wear the Microsoft logo on their blogs / resumes etc. with pride.
Microsoft is doing a terrible job at corporate communication(s) and the most frustrating part of all is that it is the actual fans of the brand that are noticing the most.
That is probably a small glimpse at how a competitive situation can motive product lines into making snap decisions the way they have been in the past five years. The reality is you the customer out there who use the technology actually play somewhat a smaller role than you do think around feature selection and roadmaps for product designs.
It's often a competitive influence that drives the most decisions and sure compete leads to innovation right and that's something we should all embrace - except if the tax is instability.
For a deeper insight into this topic around “Why” Listen to a podcast I did list week titled “Windows 8 Round Table” via TalkingShop DownUnder.