Work is highly valued in our society, and considered the best way to achieve economic security and self-sufficiency. If that is true, explain how there can be people who are “working poor”?

Work is highly valued in our society, and considered the best way to achieve economic security and self-sufficiency. If that is true, explain how there can be people who are “working poor”? How can someone be working and poor at the same time? Does this contradict our beliefs in the value of work? What are the implications when developing anti-poverty strategies?