Only 40 cities. The reality is that the best work-life balance cities are not the biggest cities in the world. You get the best in the middle range. I have been working in Copenhagen, yes, it is a nice city, but you get way better quality of life in a 100,000 to 400,000 city nearly anywhere else in Europe. Even Aahrus has a better quality of life.

The problem of these ranking is that they want to be global, so they take very big cities known by most of the people at the world level, but all the quality of life is in the middle. You will not see Münster (DE), Boulder (CO, US), Lausanne (CH), Nancy (FR), etc. etc.

They are basically the the best from the worse.