-10 on Carfax history generally means that the vehicle has a salvage title. This could be due to a number of reasons, such as the car being involved in a major accident or flood. Salvage titles may make it difficult to register or insure the car, and may also affect its value.
It is important to note that not all cars with salvage titles are unsafe. However, it is important to have a qualified mechanic inspect the car thoroughly before purchasing it to make sure that it is roadworthy.
