There's absolutely nothing wrong with it in principle. It's only that as the web grew up, and websites became less a bunch of static files and increasingly an

There's absolutely nothing wrong with it in principle. It's only that as the web grew up, and websites became less a bunch of static files and increasingly an application, or more commonly a pile of application-like messes run by many different people at the same time, involving a bunch of dependencies between files, whether organized code or haphazard things piled on things piled on things, doing staged releases comes to be the more sensible option. At a certain level of complexity, FTP can become a liability and cost you business.