It's the reason why it can only work at small scale: it's all or nothing. It wants to be your only communication channel. But, surprise, as soon as you live in

It's the reason why it can only work at small scale: it's all or nothing. It wants to be your only communication channel. But, surprise, as soon as you live in a larger organisation, there will already be communication channels that serve part of the same purpose. Then most of the functionality become clutter.