His reply to this tweet is that he didn't want to spend $20million of his own money on this venture. When you have the option to throw 20m on projects, you can spend it reasonably quickly.

His actual claim is that spending other people's money helps his focus because it makes him feel responsible. That's a plausible argument.

The first thing you want to hear as an investor is that the person you're investing into has as much skin in the game as possible so opening up with "I'm putting other people's money in this instead of mine" is not great.