In principle you have a point, but I'm going to play devil's advocate here in favor of preconceived notions. Don't forget that p.n.s, which are after all forms of categorization we use to structure the world around us, do have a purpose: to filter out information which previous experience has taught us will likely be irrelevant to us, something quite important if there is too much information out there to process. Notice Im talking about informed prejudice here, not questionable traditions (my grandfather always said Creed sucks/rules and I believe him blindly...)
So of the hundreds of perfumes thrown on the market every year, which am I going to try, how will I set my priorities? Let me tell ya, David Beckham and Paris Hilton don't have much of a chance, a new dior or Creed has.
Sure, I might miss a really great Beckham fragrance, in fact, if my preconceptions become too encrusted, I might miss the house of Beckham's transformation into a top quality house (well, other BNers would call attention to this, that's why it's so valuable to have a community like this, despite inevitable disagreements).
Well, you can't have it all. Surely an ultimate judgement of the individual fragrance must be based on trying it. And I'm fully aware what damage prejudice can do when applied to people/groups (however, cognitively, it's unfortunately inevitable). But hey, it's only perfume here and these days one can make sometimes make pretty adequate predictions about what the new XYZ is going to be like. So, I'm not going to listen to any new Britney Spears Album but will check out a new Robert Pollard release, will not try any new corn syrup plus ârtificial flavoring candy bar but will test a new organic cereal, will not order samples of any new Coty fragrance, but will be interested in a new Lutens (though it may disappoint me). And if, say, I've hated every single Guerlain out there (unlikely, I know) why should a new one be a priority?