The Annoying Frenchman wrote:
For example, when Paradise Lost released Host (their softer and more pop-oriented album) people cried that they sold out... Well, the album wasn't successful at all. On the contrary, when they came back to their previous sound, they regained sales. I don't think they sold out with Host, I think they did with Believe in Nothing by giving their fans and label exactly what was expected of them.
Just because you sold out (or rebranded) doesn't mean you were successful commercially.
Very often bands sell out because record labels demand it but the sell out is a failure. This happened to bands like Prong and Anthrax where record companies influenced the sound and style of the band but it actually resulted in less commercial success.
Concept of selling out is to branch out in terms of market scope. In Flames for example got a lot more fans by embracing Nu-Metal and Metalcore elements (remember they were touring with Slipknot and Korn when they started to change).
This got them Nu-Metal/Metalcore kids while they managed to keep some of their older fan base.
The goals of selling out successfully is:
1. Expand market scope and therefore profit and fame.
2. Not lose original fan base or replace the old fan base with an increased new fan base thus resulting in bigger fanbase, more success and ergo more profit.
Bands of course don't think in such pure marketing terms but it's clearly what they're doing.
And it can result in failure when the band loses old fan base but the new fan base (aka target market) doesn't embrace the new band.
A good example is Machine Head.
With Nu-Metal peaking, they embraced it and adopted all the trimmings of it (rap etc).
Obviously this alienated a lot of the old fan base. But it was never picked up on by the new fan base. Hence Machine Head flopped and then had to reinvent themselves as going back to metal with "Through The Ashes of Empire."
Some bands just lack the appeal or the ability to successfully change their fan bases without too much damage to their image (aka brand). Or their old fanbase has very specific expectations to accept a change in sound (aka rebranding).
Look at what happened to Cryptopsy when they turned Death/Metalcore. Their old fan base had specific expectations so most abandoned the brand with the release of that abomination, The Unspoken King. It didn't really appeal all that much to the Metalcore crowd either.
On the other hand Mastodon and Opeth's fanbase for the most part were more open to rebranding so accepted these bands going softer.
People forget that music is an industry and that bands need to be successful so they can afford to eat. And like any industry, the more successful you are, the greater the expectation of success from the record companies, the fans and the band members themselves.