Yes. Self-editing, followed by professional editing, is such an extremely important part of the writing process. As a nonfiction writer, I have not used groups of beta readers, but I have paid for professional editing, as I think good editing can make or break a book.
In terms of blog posts, knowing when to stop is also important, and it’s awesome that you write daily! If I see a typo, I’ll jump in and fix it, but I face the same issue with “hmm…maybe I should add this other topic…”
Writing is so much more than simply typing out sentences!