By far the most seen are these kinds of alone/bad relationship with family/family unwilling to care, which is the prerequisite for all bums. The middle class before the financial crisis, all kinds of overspending, suddenly the financial crisis, the loan can not be paid, the company also collapsed. Then they filed for bankruptcy with the U.S. government, and if they passed, they were penniless and lost all their assets, but if they didn't, they went into hiding. A veteran of the war, suffering from post-traumatic stress syndrome (PTSD), the symptoms are so severe that he cannot take care of himself, he has no skill, his family is not willing to take care of him, and he can't stay in the veteran's hospital (VA Hospital) every day. The family doesn't care about those who haven't received a proper education since they were young, or who dropped out of school after 12 years of compulsory education. Retired seniors who didn't save much for retirement and end up with a house they can't keep. Alcoholics and drug addicts. The family is in a bad way, with a divorce, death of a family member, or physical disability due to an automobile accident. Then, not every city has a good welfare system. In my village, for example, there is indeed a homeless shelter, but there is a limit on the number of days you can stay at the shelter. Usually it's 3~5 days, and if there are special circumstances, it can be up to 30 days. Then someone will come to assess the situation of the homeless. If it is determined that there is no need to keep them and nothing serious will happen to them, then they will be thrown out. If they need to stay, then it's a 30-day extension. And most importantly, the shelter doesn't take in everyone, only those they think they can take in. As for the rules, they vary from station to station, and Homeless Shelter can only guarantee the basic needs of survival, but nothing else. Most of the shelters are private, not run by the government. There may be only one government-run shelter in a city, the rest are private. And there's an assessment system, so it's hard to get accepted again after you've been booted out.