Paying off a 30-year mortgage in 15 years can be achieved through extra principal payments, biweekly payments, or refinancing. While this approach saves significant interest, it may impact other financial goals. Key considerations include retirement contributions, emergency funds, and existing high-interest debts. Making extra payments or switching to biweekly payments can reduce the loan term, while refinancing to a lower rate can also expedite repayment. However, homeowners should weigh the benefits against potential lost investment opportunities.