Your brand is not your logo
Cluelessness on the half shell.
Smart marketers understand that a new logo can't possibly increase your market share, and they know that an expensive logo doesn't defeat a cheap logo. They realize that the logo is like a first name, it's an identifier.
So, when Pepsi and BestBuy start 'testing' logos, and proclaiming that a new logo might change their market share, I get nervous. You can't test a logo any more than you can test a first name. Sure, you can eliminate Myxlplyx as an outlier, but given the success of the Starbucks mermaid and the Dunkin Donuts typeface (two outliers) you can see that this testing is sort of meaningless.
I guess the punchline is: take the time and money and effort you'd put into an expensive logo and put them into creating a product and experience and story that people remember instead.