Comment by thinkingemote

They undergo intensive training for weeks before. Scripted, rehearsed, perfected, trained. I've witnessed it. There's not much space for natural expression in these talks. Everything is choreographed. Where to walk, look up, wave hand, smile etc all planned!

The stiffness is because the presenter is mainly a techie, developer or manager and not a natural performer. Their bodies are resisting the conformity by conforming to the letter but not the spirit.