If you had a $300,000 mortgage that was financed over 30 years, of which there 10 years left, and all of a sudden borrowing rates were at 2.39%, then instead of refinancing your home at 2.39% for the 10 year period that was left, you would pull your money back out and refinance your home for the full 30 years again, provided you could reinvest that money at a higher rate of return than what you would be paying in interest. You would still come out ahead every day, right?
On May 19th, 2016. See this statement in context.