A couple of decades ago issuance assessors were given the time to do proper detailed reviews of damaged cars.
It seems in recent years - probably due to the plague of cash for cash - it's turned into a conveyor belt where they don't really spend much time looking in detail - it is just their opinion from a brief review.
Sometimes the categorisation is accurate, other times cruelly wrong where perfectly good cars that should be given an N get classified as an S - it could be suspension and panel damage, but no actual chassis damage.
Either way a recovered car will always carry a stigma - automatically reducing its market appeal - and this should reflect in price.
But it still can be a good and perfectly safe car, just at a reduced price - Good luck with sale.