While Microsoft stock is not going up, it is unclear why. The company has, over the last 10 years, over doubled revenue and almost tripled profit. And it did this in an environment where they held 80+% of their primary market. This requires innovation and growth into new markets since you can't grow much when you already have 80+%
Looking at Apple, they have done well. Made products people want. Gained technology to product price competitive products. But the real point is that they were under 3% of the market and now are at 12% or so. Microsoft still is over 80% but the point is that growing by 9 basis points for Microsoft would be just over 10% but for apple it was 400% growth. In fact, there is no way Microsoft can grow more that 25% in their primary market as, well, that would put them at 100%, The growth potential is almost all in other markets and new technologies. Apple, on the other hand, has tons of room to grow into if they can take more market share. However, if you look at their actual financial data, it is the new markets that really pushed them forward over the last 10 years. They executed very well in identifying new opportunities and taking the risk to enter those markets at the right point.
Microsoft is currently, I believe, undervalued. Microsoft does have some very bright people and some compelling products coming, And they continue to be stable too. Not that Apple is not in a major growth spurt, but they are also valued relatively highly compared to earnings.