Simple fact is Microsoft don't currently care much about global market share.
Not sure you how you come up with that, Market share is the largest thing when it comes to smart phones. As others are saying, one of the larges problems right now and as always been on Windows Phone is the Apps. Yea some people have all the apps they need or feel happy with just using the web site.
Edit: Wanted to note here, this is STILL the problem after about 5 years on the market, not released last week.
The fact is, we still have almost No local apps (TV stations, Radio stations, Local stores, etc), Bank apps are fading, and if you are with a smaller bank, guess what ? Then we have odd ball apps that devs still feel it's not worth creating an app because of amount users.
Then we have apps for companies that don't even promote it. For example, for the now pulled, Bank of America app, from Windows Phone 7 we had an APP for BOA but, if you ever watched their commercials on TV and they promoted their mobile apps, never once did a see ANYTHING about Windows Phone, just Android and iOS. Same with Home Depot and about 20 others. No promotion AT ALL.
You can see everyone talking about apps in this thread, if you don't think it's a problem, GOOD FOR YOU, it's not that case for everyone. Talk to anyone on the street who is fairly techy and tried Windows Phone, ask them what they like and dislike about it. 90% of them will say, they like it for the most part (accept for the fanboys, but, open mind people), 99.9% of them will say there is STILL a problem with the apps.
Anyway about this the ONLY way this can be fixed is by Market Share. And yes, this is one of the TOP things on Microsoft's Windows Phone list. It's one of those catch 22 things, You cant get the customers because you don't have the apps but, you cant get the apps because you don't have the customers.
Ask yourself, why is Microsoft only making a crap load of low cost Windows Phone devices but, no high end models, you know on the hardware end, they are not making anything ? It's about market share, plain and simple as they know the largest seller for smart phones is low cost models.
It is about market share and it IS one of the most important things that Microsoft needs to achieve here to be successful.