Statements to Insurance Company
You will be making statements you shouldn't be making to the insurance company. They may ask you what your injuries are, and you may not know the full extent of your injuries. When the injuries manifest a few days or weeks later, the insurance company will tell you they won't pay.
Multiple Insurance Policies
A very high percentage of the time there is more than one insurance policy available. The person trying to settle the case without a lawyer only knows of one policy.
You get 11% of the Settlement a Lawyer Would Get
According to a financial analyst at one of the top insurance companies, unrepresented parties or "Unreps" as they like to call them only get 11% on average of what represented parties get.