'Most people have terrible passwords, and WiFi is no exception. Your WiFi password is your primary line of defense against unwanted access to your network. That access can result in a whole host of other nasty things because an attacker can monitor the traffic on your network and even gain direct access to your computers.

The best way to prevent such an intrusion is to use the same tools an attacker would to test the security of your WiFi password.

[...]

Remember this process should only ever be used to test your own security. Using it on someone else's network is illegal.'

-- source: https://linuxconfig.org/use-aircrack-ng-to-test-your-wifi-password

Cheers, Peter