Think of it from a coding point of view.
Many people think that some developers write code directly on production, to their personal style, and thats it. That certainly happens.
Other teams have coding standards, style standards. Tabs versus Spaces. CamelCase for Class names but something different for variables?
The commit their code, and do a pull request and someone else reviews it. Edits are proposed or demanded. Code is reviewed again, then maybe it goes to production. Its been known for production code to have issues, but generally after going through a process most are prevented then if the developer was able to merge in code without review.
The larger orgs I mentioned have a involved editorial process for editing stories.