The problem with Beats headphones are that they're overpriced, I think most people can agree that they have good sound quality but they're not worth the price.
Still I don't think it was worth paying $3 billion for Beats and obviously it was more because of the streaming service and executives with inside connections to the music biz (Dre and Iovine). Still, the only reason this acquisition happened is because, unlike Steve Jobs, Tim Cook doesn't really get music the same way he did so he essentially hired people to fill that void.
That is my main problem with Cook, since he doesn't have nearly the level of vision and involvement that Jobs had with the products and services being developed under him, he just sticks to being the average CEO and expects everyone to know what they are doing and most likely provides no input and just says yes to whatever ideas are pitched to him.
This is basically how I view Tim Cook when being pitched with the iPad Pro/Apple Pencil, iOS 7 redesign, Apple Watch, etc: