Earlier, Microsoft had the vision of ‘Windows across each desktop’. Over a period of time, when it made forays into tablet devices and mobile phones, the same vision persisted and morphed into ‘Windows interface across all devices’. This lead to the Windows experience (including the Start menu) being replicated across all gadgets, irrespective of their form factor (primarily mobile phones with their small screens).
After the iPhone was released and smart phones became the rage (along with tablets), Microsoft released Windows 8, with mobile and tablet devices in mind.
While in the earlier case, the ‘desktop’ metaphor was extended to mobile devices, with Windows 8, the ‘touch’ metaphor was extended to desktop systems – once again without giving much thought of relevance and usability.
In both cases, I feel that these decisions of ‘extending’ philosophies across varied devices and gadgets resulted in slow to near non-acceptance.