Why some people become homeless ?

There are many 'reasons' of homelessness. Mental health issues, addictions, lack of social support, lack of family/friends to help, physical disabilities, difficulty obtaining and maintaining employment, lack of education, domestic violence/abuse, companies downsizing and/or going out of business, too many applicants for jobs, low wages compared to housing costs, Veterans transitioning back into civilian life/Veterans with no support/Veterans with mental and physical health issues, the list goes on and on.
I really like the Housing First approach. It also coincides with Maslow's Hierarchy of Needs.