Why aren't software companies releasing their products for Linux?

I have recently developed an addiction for AskUbuntu. The Ubuntu Fora have always been my preferred lieu d'exchange with the community, where I dealt with the initial struggles of a novice user trying Ubuntu on a novice piece of hardware. One day though a particular issue proved harder to solve than usual; out of despair I ended up leaving a question at AskUbuntu. Although not entirely convinced with the apparent community division along two different crowd support technologies, I finally got a solution there.

Some weeks ago I ended up at AskUbuntu again from some random web search. Lo and behold, alongside my user name there were these numbers and a funny icon. It happens the question I left had in the mean time got over 1 000 views; in consequence I was warded reputation points and "badges". Isn't that just great? In the fora only the number of messages is recorded, there is no interaction quality feedback. Suddenly AskUbuntu became a challenge, and I end up spending 10 or 20 minutes everyday helping anyway I can: answering questions, editing, commenting, all along piling up reputation points (this is in essence how a gift economy works, but I'll leave that for another time).

One of these days a user left a question that I imagine many Linux newbies probably have: why aren't software companies publishing their products for Linux? The answer was a bit longer than usual, thus worthy of logging.

Here's the original question from user191025:

I've been following Linux since the late 1990s. Here is my question: First, why cannot Microsoft Window applications and programs software companies start making their proprietary arts and crafts compatible with Linux?

This is not be a rhetorical question, but of frustration for how we, the people, do not want to petition big business for another option/choice such as open source Linux.

Thank you, and for the record, I am an inventor and an investor too.

Finally, how may I help expedite this necessarily and sufficiently?

And here is the answer:

This question is not related to Ubuntu per se, but might be worthy of an answer. Software companies relying on proprietary licensing are usually focused on short term profits. They thus perceive the market as is today, the vast majority of desktop users run Windows, the others operating systems have such small market shares that are not worth the bother. These companies will only embrace Linux when its market share becomes visible.

Android is on track to change that, at least on the mobile market. There are today a thousand million users out there with an Android device, potential clients for your software. If your business model relies on proprietary licensing for mobile applications you have to target that market.

There is another point though: the expansion of Linux desktop has also brought an expansion in open source desktop applications. There are few things today that you can do on Windows and not on Linux with equivalent open source software; this is usually the case only in narrow market niches. Thus many software companies regard the rise of desktop Linux as a threat to their proprietary licensing business model, and try to delay it as long as possible.

My impression is that this state of things is about to change with the merge of desktop with mobile computing, what Canonical terms Convergence. If I had the resources and will to invest in the future of computing that's where I would be.