At what point did Yahoo’s core business start to shrink or get the stench of being a loser? I have to imagine that Yahoo! acquiring them was a stinker for their

At what point did Yahoo’s core business start to shrink or get the stench of being a loser? I have to imagine that Yahoo! acquiring them was a stinker for their users. Did anyone think of Yahoo as bringing strategic value to the services they were acquiring? By the time they bought delicious and tumblr they had a track record with flickr and any of the users of those services saw the acquisition as a negative.