Some loans penalize you for paying early, and refinancing your home loan can result in a penalty for prepayment.

What happened is that a lot of less-than-scrupulous mortgage brokers sold good for 2 or 3 years mortgage teaser rates, when rates would rise, often beyond 4 or 5 points from the rate of the normal housing market.
In different circumstances refinance mortgage rates in force may also become significantly lower than when you bought your home.
Some also use refinancing to switch from a fixed rate mortgage terms to a variable rate or from a variable to a fixed rate, for one reason or another.

You get more time to repay your mortgage loan at low rate, which is like a boon in these difficult times.

When looking for a lender ready to provide all the information about your loan request and investment.