jaxwired:Clare Newsome: No, the product didn't physically change, but its ultimate value did.
Every star-rating we give is based on a comparative, performance-per-pound basis. That means as newer, better (and better-value) rivals appear, products can lose their position.
Star ratings can also fall (or, indeed, rise) as their prices change and therefore their position in the market alters.
That's the same answer I came up with before I posted. I'm still not a fan of demoting products. It seems to arbitrary.
It's not arbitrary at all. The star ratings are relative to a product's competitors in the same category, if those competitors introduce a better product it affects all the products in that category.
BTW, I can't recall a product ever having it's star rating increased...
I can, a pair of KEF floorstanders I think, a year or so ago, WHF reviewed them, basically said they were awful, gave them 2 stars (I think, might have been 3), KEF were understandably concerned and then realised they'd sent out a pre-production pair that were not the same as the ones on sale (different crossover I believe), sent a new pair for review and they went up to 4 stars.
There's far less opportunity for a product to increase in stars, it would require a competitor to withdraw from the market (and presumably not replace the product they were withdrawing). I could have happened with the TV section when Pioneer pulled out, but I don't know if it did or not.