It is highly recommended that you prepay as much of your mortgage as possible every month, which will drastically reduce the total amount that you pay.
However there are times where this could be disadvantageous.
If you are in a situation where you don't have funds to cover three to six months of expenses, it is recommended that you save that amount before you pay additional amounts on your mortgage.
If you have a large amount of credit card debt, over the long run, you will save more money by knocking down those high interest loans first.
There also may be times where that money would be more wisely invested in the market, depending on the expected rate of return versus how much you would save in early payments.