Of course you would use your own website, but you understand it in a way your users don't. From experience I can say you won't anticipate many of the ways thing

Of course you would use your own website, but you understand it in a way your users don't. From experience I can say you won't anticipate many of the ways things could go wrong. Some of that can be done by recruiting individual test users to observe, but aggregate stats on usage are also incredibly valuable to understand how people are using the site, where they get stuck, what features are important to them, and more. There's no need to identify particular users, but tracking user behaviour in general is incredibly valuable when operating a serious website.