layout – Is there a reason for the discussion to be reversed in the threads?

In all email clients I know, when someone answers an email, the answer is written at the top, above the original email.

I do not understand the reason for this choice. It seems that:

  • For any email long enough to require a vertical scroll bar, I need to scroll up the screen before responding.

  • It is very difficult to read a discussion with several emails. I have to read a text from top to bottom, then go to the top and find the beginning of the following message.

  • It's just counterintuitive. Books, scientific articles and web pages are written from top to bottom. There is no chapter 1 at the end of the book, and the last chapter at the beginning.

What would explain this original choice? I mean, since someone, around 1985, came up with the idea of ​​doing it that way, instead of using a usual paradigm used for existing content such as books, it There was probably a good reason for that. Or was it purely technical?