If an angel loses all of their money on their prior round of investments, they will have no more capital to invest in that "single best investment" just around

If an angel loses all of their money on their prior round of investments, they will have no more capital to invest in that "single best investment" just around the corner in the next round. That is why they insist on onerous terms--to keep them in the game. And because no one can predict the future, they must give the same onerous terms to that one "moonshot success" which will give them their 3000x return. They simply don't know which one it is in advance.