One criteria that may soon see a resurgence in popularity is that of morality. [1]
[1] https://www.currentaffairs.org/2017/06/its-basically-just-im...
[1] https://www.currentaffairs.org/2017/06/its-basically-just-im...
It's fine if the wealthy choose to give away some or all of their wealth, but it must be voluntary. Anything else is called "theft" - or the closely related concept of "taxation".