There are other reasons to not pay off you mortgage, especially in the US. The two most prominent being:
1. Usually a certain amount of equity in the house is protected by state law (varies from state to state). So if someone sues you and/or you go bankrupt, no one can touch your principal residence provided your equity in the home is below the state's threshold. That is assuming you stayed current on your repayments and the bank is still good with lending to you.
2. No recourse loans. If you pay off more earlier, you are just opening yourself up to further risk. I'd much rather lose a bit on super low interest rates (and maybe a little in lender's insurance, too), than lose out if the housing market crashes.
1. Usually a certain amount of equity in the house is protected by state law (varies from state to state). So if someone sues you and/or you go bankrupt, no one can touch your principal residence provided your equity in the home is below the state's threshold. That is assuming you stayed current on your repayments and the bank is still good with lending to you.
2. No recourse loans. If you pay off more earlier, you are just opening yourself up to further risk. I'd much rather lose a bit on super low interest rates (and maybe a little in lender's insurance, too), than lose out if the housing market crashes.