Overall a good collection on the complex systems, somehow it missed the part how complex system came into the existence in the first place itself.

> Human expertise in complex systems is constantly changing

I feel this is single most important factor responsible to both making system complex and at the same time improving them depending on who the people are and how they take failures and breakdowns. I find it funny but we are in an era where folks building ML systems do not seem to remember the direction in which to open the screws. They do have clear expertise in something new but clearly lack in some other areas