Conventional wisdom says it’s better to buy a home instead of rent. There are exceptions to this rule, but generally over a long period of time, it is better to spend your money, time and effort on an asset that you own instead of one someone else owns.
Traditionally, authors are in charge of writing the book and the marketing job is left to publishers and publicists.
If you leave it completely to other people to sell your book, what asset do you have once the whole process is done? All of the money you spent on the publicist and publisher is gone and you have nothing besides book sales to show for it. The next time you have a book come out you have to spend the exact same money to reach the exact same people. And considering how quickly the markets are changing, you will more than likely spend the same money to reach fewer people.
Is there a better way?
By building your own tribe you are creating something that will help you for the rest of your career. By gaining permission to stay in direct contact with your fans, you will be able to grow a relationship over a long period of time that will not only help book sales, but also your speaking career, consulting company, products sales or whatever else you plan on doing in the future.
Where do publicists and publishers fit in?
Depending on your goals and resources, publishers and publicists can still be a significant asset in selling your book, however this should be done in conjuncture with building your own permission list. Make sure the work they are doing to sell your book also builds your own online platform.
Your goal should be to build your online platform to the point where it alone can sell thousands of copies of your book.