Beta readers are people who read your book after you’ve finished one draft but before you start the next one. They help you spot the big errors, inconsistencies, continuity problems, and general mistakes so you can polish the subsequent versions and make your books shine. They help you write a better book, and over time make you a better writing. But that’s not the most important reason you should have beta readers.
The most important reason you want a beta reader is as follows:
They Aren’t You
By the time you write, rewrite, mangle, spindle, and otherwise herd your words into a complete book draft, you are no longer qualified to tell if it’s good or bad. You’re too close to it. You’re fatigued. You know each sentence too intimately. You need new, fresh eyes on the draft to tell you what you’re missing.
Bottom line: beta readers are important to the process of your writing, the quality of your book, and thus the success of your literary career. You’re going to want some. Here then, are the who, what, when, where, why, and so what of beta reader mojo.