Beta readers are my most valued resource from the beginning of writing my novel, straight through to the end. I suppose each and every writer has found the best method for themselves, but I've no idea where I'd be without this golden crew of varying opinions.
The first order of business I had to learn, was accepting criticism in the spirit in which it was given. If I was going to grow as a writer, I needed input, and it couldn't come from between my ears. Granted, my muse is the finest in the world, however, there are checks and balances. Hence, my beloved beta readers!
For example, as I'm underway with the second in my detective series, I'm finding an interesting situation-that of the re-introduction of my characters from the first novel. I had one reader go through the first chapter, and he had no problem with it. Of course, he'd read the first book. So, I had someone else read it, and she said she wanted to know a bit more about the characters. We both simultaneously said, "Read the first book!"
It was a great point which led to an interesting discussion of how readers select books, either online or in bookstores. The gist of one may not interest the reader, whereas the other might, but the reader needs to know about the characters without boring other readers who are following the series. The job of us writers is to keep the introduction, or re-introduction of characters as interesting as we possibly can. A challenging task. I like challenges.
Thank goodness for my beta readers!