[jrcplus]

I worked at Skype from eBay to Microsoft. The clients were rewritten, sometimes from scratch, sometimes redesigned to chase after the latest UI trend. But rewriting clients didn't address the fact that the OG widely successful Skype was fundamentally peer-to-peer. There were no servers, only supernodes.

After smartphones took off, management was reluctant to ditch P2P and move to a client-server model, for both business (running servers costs money, and remember Skype mostly made money on calling PSTN) and technical reasons (P2P was at the heart of Skype). Internally, engineers had Skype working "in the cloud", but it took years of waffling (middle management was distracted by the introduction of Scrum; don't get me started about that; upper management was distracted by the company getting bought and sold twice) before slowly turning around the big ship.

By then, the A/V part of the tech had become commoditized, and plenty of free alternatives (namely FaceTime, WhatsApp, Messenger, Snapchat) had appeared on the scene, with better business models. No amount of rewriting code and building from scratch addressed that latter part. Management was very interested in finding new ways of making money, but it was also (for better or worse) very reluctant and careful in introducing ads into the UI.

[niutech]

Why not open source Skype then?