When someone remortgages their home, what they are doing is getting a new loan on the property to replace the original mortgage.  This is not a second mortgage.  When remortgaging, the new loan pays off the old one so that there is still only one mortgage on the home.

Most people who remortgage their homes do it to get a better interest rate.  That is usually not the case in a bad credit remortgage, however.  This type of mortgage is usually entered into by people who are struggling with their bills or perhaps even behind on their mortgage payments.  Some lenders target homeowners in these situations because they know that many homeowners facing financial difficulty will agree to outrageous terms to avoid losing their homes.