People who have seriously contemplated know whether or not they are happy and weighed the options. At some point you say screw it. If you have goals or aspirations, dreams and can't achieve them then why keeping doing mediocre crap and be miserable. That is settling for 2nd..3rd etc. among other crap going on in their lives.
I hate people that think they have a right to decide for others what I want to do with my life. Maybe consider the fact that the person weighed available options and that is their choice and hope that they find another route.