I couldn't find any answer regarding this specifically, so I assume there's some basic concept behind this that I missed.

So, as far as I know:

Modern modes are based on the same set of intervals, as seen in this picture.

[![enter image description here](https://i.stack.imgur.com/83R1r.png)](https://i.stack.imgur.com/83R1r.png)

To play in a modern mode you would just have to start from a different degree of that set of intervals, and you would have a mode.

This evokes my curiosity: why is this pattern so crucial? After all, a scale can be composed of any allegedly random set of intervals. 
So how did this specific pattern came to be? And what explains the adherence to it, compared to going full on crazy and using interval patterns that are remotely different from this pattern? (In western music, at least.)

Thank you for your time.