I have heard Natural England accused of moving the goalposts in terms of defining favourable condition of Sites of Special Scientific Interest. However, if you wanted to find European-scale instance of strange conservation assessment, there's one right here.
Saga pedo is a whopping great carnivorous cricket.
Thing is, you don't get Saga pedo in the UK. Never have done. Can continued absence be described as favourable condition? I guess at least you could say things haven't got any worse.