Is it smart to quit your job to work at a temp agency?

My husband currently works at Target(has worked there for about 15 months), in the stockroom making $9 an hour. It is not a full time job, he would be lucky if he even got 30 hours of work each week, the weekly hours are not consistent, he thought he would be guaranteed 40 housr each week when he got hired, but he only works 16-24 hours. And when the store does not make their goal for the month, hours are cut. He has been looking for a full time job working at a warehouse for about four months now and has not had any luck. He is very relaxed and chill about the situation, unlike me I am more aggressive. Anyway, I keep telling him that he should go to a temporary agency, and even though you will be temporary that you would be working full time and after three months you could become permanent. He does not like the idea, he thinks it is too risky leaving his job to go to a temp job and so does his parents....but of course they will they grew up in a time where stability was very important in a job, his mom has worked at a hospital for 25 years, his dad has worked for the city for 20 years. Nowadays, you cant get that kind of stability in jobs, most ppl dont even make it to retirement without being laid off at 50 years old or right before they retire. Off in a rant I go, so anyway, is it a bad idea that he quit his part time job to take a job at a temporary agency, where he would be working full time? Or am I not thinking with my head?