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system
how is not paying off mortgage better in normal circumstances?
user
lets do the math, using your numbers. we start off with $100k, a desire to buy a house and invest, and 30 years to do it.  scenario #1 we buy a house for $100k mortgage at 5% interest over 30 years. monthly payment ends up being $536.82/month. we then take the $100k we still have and invest it in stocks, earning an average of 9% annually and paying 15% taxes.  scenario #2 we buy a house for our $100k cash, and then, every month, we invest the $536.82 we would have paid for the mortgage. again, investments make 9% annually long term, and we pay 15% taxes.  how would it look in 30 years?  scenario #1 results: 30 years later we would have a paid off house and $912,895 in investments scenario #2 results: 30 years later we would have a paid off house and $712,745 in investments conclusion: not paying off your mortgage early results in an additional $200,120 in networth after 30 years. that's 28% more. therefore, not paying off your mortgage is the superior scenario.  caveats/notes/things to consider play with the numbers yourself:
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