The idea was that they would help advance the mortgage market by buying up mortgages from mortgage originators and therefore allowing them to make more mortgages.

其主旨就是通过,从抵押贷款的原始权益人手中,购买这些债权来促进市场的发展,那些原始权益人就可以去放更多的贷款

耶鲁公开课 - 金融市场课程节选

The subprime mortgage market was bringing people into the mortgage market who in prior decades would not have been involved-- would not have had any mortgage.

次贷抵押信贷市场,把十多年前那些,不能获得抵押贷款的人,带进了抵押信贷市场

耶鲁公开课 - 金融市场课程节选