Why does taking a band seriously mean looking at it like a business?

Most of the successful artists I have seen follow this path:

Get amazingly good at music -> An audience starts to show up and spend money on the music -> then the artist learns just barely enough business so they can deal with stuff as it happens.

It's like 90% music, 10% business. its not about it giving it 100%, it's about giving it 100% without letting business get too much in the way