It's what politicians and other so-called "elites" do to show their peers--as well as us ordinary, hard-working, tax-paying folks--that they're enlightened and think all the right thoughts. This is intended to prompt other elites to conclude that any policies being pushed by the signaller must be similarly faaabulous and enlightened.
So for example, European politicians wanted to show their peers how enlightened they were, by inviting millions of middle-easterners and north-Africans into their countries. They push this policy by claiming--falsely--that "most" of the refugees are women and children, when in fact the overwhelming majority (80 percent or so) are 20-to-30-year-old males.
The fact that a big percentage of the so-called refugees have shown an eagerness to assault European girls and women, and to steal anything available, and to collect money from host governments, is irrelevant to the virtue-signalling pols. In fact they're even willing to kick their own citizens out of their apartments to make room for the immigrants.
Some virtue, eh?
But hey, your security as a citizen is trivial compared to the ability of pols to feel virtuous.