It's just not a great protocol. Many years back I was working on a desktop client for XMPP. The first problem I encountered was that XMPP does not actually se

It's just not a great protocol. Many years back I was working on a desktop client for XMPP. The first problem I encountered was that XMPP does not actually send individual XML documents each time it sends a message. Instead it starts with a tag that is not closed until you actually turn off your client and close the connection. So you couldn't use a simple XML document parser for those relatively simple messages as it would read the start tag and never finish, but had to do some kind of streaming-based thing.