All my financial projections have a budget line totalling at least 20% of revenue called “Margin of Safety.”

It comes from Warren Buffet’s business partner, Charlie Munger. The idea being:

“When you build a bridge that can hold 30-ton trucks but only drive ten-ton trucks across it, you would never want your fortunes to be dependent on everything going perfectly, every assumption proving accurate, every break going your way.”

I’m going to be okay even if everything doesn’t go my way