Car mechanics tend to call the rust in your car “rot.” It is a similar term being used to perishable goods like fruits and vegetables. When left unprotected, this rot could damage the entire product. For cars, rust is the rot that could fully deteriorate its quality and performance.
Of course, if you are timely and responsive, treating car rust is pretty doable. It is not difficult, either, especially if you have the right tools at your disposal.
However, if your car is already covered in rust, is it still worth fixing it?