Logout of HN. Click 'add comment'. Use the 'create account' boxes instead of the 'login boxes' to create a new account. Done. What's wrong with that approach?

Logout of HN. Click 'add comment'. Use the 'create account' boxes instead of the 'login boxes' to create a new account. Done. What's wrong with that approach? It's as easy or easier than using email, which I may or may not be logged in to.