Still doesn't answer the question. Why does one owe taxes if at the end the accumulated and deferred "profit" turned out to be a loss?
(Chat GPT) In the event of a foreclosure, the tax implications can be complex and depend on several factors, including whether the mortgage is recourse (the lender can pursue the borrower for the difference between the loan balance and the foreclosure sale price) or nonrecourse (the lender's only recourse is to repossess the property and sell it to recoup their losses).
Generally, for tax purposes, the amount realized from a foreclosure is considered to be the fair market value of the property at the time of the foreclosure, plus any debt relief the borrower receives. This amount is compared to the property's adjusted basis to determine if there's a gain or loss.
If the mortgage is nonrecourse, the entire amount of the loan is considered to be the amount realized, even if the fair market value of the property is less than the loan balance. This could result in a taxable gain.
In the case of a 1031 exchange, if the property is foreclosed upon before the investor sells it, the foreclosure is treated as a sale, and the deferred taxes from the original exchange would be due. The amount of the tax would depend on the amount realized from the foreclosure and the property's adjusted basis.