When I started out as a brand consultant one of the most important mantras I heard was "Your brand is your promise." (The other was, "You have a brand whether you like it or not.")
In the commercial world, branding is clearly an activity undertaken for financial gain. Companies portray an image, hope to pay less for the image than what you take away from it, and pocket the difference between the two.
Personal branding is different. It is commonly thought of as your professional image, e.g. that you make yourself seem competent, confident - the kind of person someone would want to hire for their work skills.
That is part of it. But there's also a personal integrity part, and that part is much more important. If your apple is rotten at the core then nobody wants to do business with you.
All of us say that we are moral people. But our actions speak to whether we deliver. The consistency (or lack thereof) determines our brand.
If you look at personal branding as a moral enterprise, the terrain regarding brand-building becomes extraordinarily complex, sensitive and challenging. Not because most adults require guidance - most of us can tell right from wrong. But because we know that saying and doing are two completely different things.
So I think of branding as a spiritual thing. It is not easy or convenient. It may even be a career-limiting move. But it does feel good to be the kind of person you'd want to have working for you, if you had to check their references.
* All opinions my own.