1) 100% of a 10M exit = $10M
2) 10% of a $100M exit = $10M
3) 1% of a $1B exit = $10M
Path is (very) arguably the easiest on the $100M exit? You likely raised outside funding, had a big enough market, grew your team and didn't have to slow-play everything, and still get a decent exit. Paid yourself some salary during that time. As the article says, lots of M&A in the ~$100M range.
$10M exit - a lot of risk, probably slower growth, bootstrapped, etc. Tons of small exists happening at that level too, but also more competition.
$1B exit - personally this seems hardest, even if probability of each occurring was the same. The size of team, scaling issues, etc all required. Of course you'd almost definitely own more than 1% at IPO.
Then stack your odds of success against those figures. Still feels like $100M is the optimal balance of risk/return.