. - If I mis-enter information into a form, your error handling forgets all my information and I have to re-enter it. This was fixed in browsers years ago when

. - If I mis-enter information into a form, your error handling forgets all my information and I have to re-enter it. This was fixed in browsers years ago when they started keeping form state along with page history. I can refresh this page, go back and forth in history, and this text box will keep my comment. Ironically, websites that tried to be clever about form state management and faked page transfers (like ASP.NET WebForms) didn't benefit from the fixes and currently are significantly worse off in terms of usability than websites that used vanilla forms. I think there is a lesson here.