Every situation is different, but generally, creditors will take aggressive action to collect the money due to them. If you don't pay your mortgage or home equity loan the lender can foreclose and take your house. If you don't pay your real estate taxes, the town or city can put a lien on your house and/or foreclose.
Credit card and loan creditors can file lawsuits against you in court. Once those creditors obtain a judgment they can seek to collect the debt through wage garnishment or bank attachment. They can also put a lien on your house or other real estate.
If you don't pay your auto or truck loan the creditor will usually repossess the vehicle, sell it at an auto auction for well below its retail value-apply that small amount to the debt, and sue you for the balance. Upon obtaining a judgment, they can garnish your wages, attach your bank account or put a lien on your house.
If you don't pay your Federal Income Tax, the IRS has special collection powers. They are not required to bring a lawsuit. They can attach your bank account, put a lien on your property, or garnish your wages-all without ever going to court. Also note that while other creditors can garnish up to 25% of your take-home pay, the IRS can take 100% of your take-home pay.