It would totally depend on the career of the person wanting to go back into the work force. I don't know what your profession does exactly.
Do laws change over time where you would need to go back to school for a semester or two to learn new laws? like a CPA would?
Do you have a certification that is expired? Out of date? My husband taught at the local vo-tech, he taught Computer A+ certificated classes. If someone in this area called HP and said my computer has crashed, it's under warranty, where do you want me to take it under our contract?
My hubby was registered with the company to work on their computers. He knew how to build them from the ground up so he could take it apart, work on it, put it back together and know exactly what was wrong.
He left the vo-tech to work in a higher line of IT for a company.
If he had been staying at home, now wanting to go back to work he'd basically have no degree due to not having taken any classes to see what new laws had been put into effect and what new technology had been developed.