He sold a giant chunk of Tesla shares weeks before the price cratered. It was ostensibly to raise cash to acquire Twitter. But now that he's trying to claim shenanigans and walk away, it's beginning to look more a way to evade insider trading charges.

Yup. Above a certain height, you start drinking your own kool-aid, the people in even your closest circles turn into yes-men, and the world increasingly appears to revolve around you. It's impossible to avoid the hubris that comes from this. And this effect resists even the best efforts to "stay grounded".

Eventually your answer to the "why" becomes simply: because you can.