A lot of the dodgy stuff is because there are a lot of internals that haven't really been changed since it was Office Communicator 2007. I've spent far too muc

A lot of the dodgy stuff is because there are a lot of internals that haven't really been changed since it was Office Communicator 2007. I've spent far too much of my life dealing with these oddities, and I'll assure you, it is a trainwreck. If you want to really have fun, write software that uses their terrible SDKs to plug into and extend Lync/Skype for Business. Still, since it's bundled with Office and Office365 Exchange, lots of people are using it and dropping SameTime or XMPP or other options in large corporations.