What Happens If You Don't Service an Automatic Watch?  Maybe nothing.  It might never need servicing in your lifetime.  An automatic watch movement could run for decades and never need servicing. It does happen. Of course if the timing gets out of spec for the movement model it will need servicing.  It could just need an adjustment or possibly a complete overhaul.  So unless your automatic watch movement is giving some type of problem no service is needed.