Yes ALT-A were the No Income, No Job, or Asset loans that helped coin the phrase “if you can fog a mirror, you can get a loan.”
I think they basically assume the people applying for them have good credit. The alt refers to them being “alternative”.
In other words they’re gay.
Seriously though, the default rate on these could be worse than sub-prime. Realtors/brokers would say these are for people with fluctuating incomes like actors or entrepreneurs, but not in recent years. Unless you replace actor with teacher, and entrepreneur with house wife.