What is one of the most straightforward description for the reality that Windows applications are not Linux - suitable?

Well, first off, there is Wine.

Second, it is (in other words) due to the fact that the applications make use of system features, and also each system is various, so they are not suitable.

You can make use of the "human language" as an example.

Windows programs talk with Windows OS making use of the Windows API, the API resembles a language.

Linux programs talk with the Linux OS making use of an additional language, the Linux API. Linux does not "speak" Windows API, Windows does not "speak" Linux API.

There are means to make Linux recognize Windows API, like mounting Wine as a translator.

How around an auto comparison/analogy? All auto coincide, yet some usage Unleaded gas and also some usage Diesel gas. You can not run diesel in an unleaded engine.

To boost the "human language" example a little :

Every time a program requires to display something on the screen (a window, message, image, food selection, switch ...), read a documents from disk, connect to a network, make an audio, do something when a customer clicks the mouse or when the customer kinds something, every single time a program requires to do that, it has to ask the os to do it. Actually, talking with the os is what a program does a lot of the moment.

Both Windows os and also Linux os can do every one of that conveniently, yet given that they were developed by various individuals, they both do it differently as well as additionally the program requires to request for those solutions differently. The languages that Linux and also Windows talk are entirely various.