There is always a talk about the overwhelming marketshare of Windows on the Desktop - which is in decline - as compared to Linux, but absolute silence and being dumb, deaf and confused on any topic of Windows Mobile marketshare - smartphones, tablets and notebooks when compared to the "overwhelming" dominance of Apple and Android in these mobile categories.
Professional and productive Desktop Linux use in USA and particularly in Europe, Asia and South America is quite satisfactory since there is fortunately significantly more "inherent" security, reliability and performance in popular Linux that is proven, more than any iteration of Microsoft Windows. In fact Windows 7, 8/8x and Windows 10 have drawn several features and functions from Linux that were available in most Linux distributions for more than 10 years.
While Windows 10 may have gained approximately 5% of the Windows desktops so far, it is very unlikely, albeit almost impossible for Microsoft to gain the 3 plus billion Windows 10 installs in 3 year period as ultimate goal. One notable reason is ban on Windows in Russia (population approx.25 million) and substantially in China - population 1.3 billion.
Already all Windows mobile, including Surface Pro 3 sales have declines recently while Apple and especially Chinese based Android devices, FirefoxOS (Linux based) devices have substantially increased their marketshare again this summer.