If you want to create a new Product, you need a name for it. Assume you have a list with 5 possible names. You are asking a couple of people which name they would choose. Some of the people will ask you what your product is about. But that is not so important.
What have Yahoo or Google to do with Search? Of course everybody is associating Yahoo and Google with Search. But that is just because of the branding in the last years.
And what’s about Audi and Mercedes. The same like with Google and Yahoo. And what to hell have Heroku to do with an AppEngine. Just from the name, nothing. But every Ruby on Rails Developer in Silicon Valley nows Heroku. It’s just because of the Branding.