I'm a big proponent of the Design Thinking / Human Centered Design framework. For those who aren't familiar with it: it's essentially taking the principles that the best designers use to create world class products, and applying it to larger scale problems.
If we take this type of thinking to its logical conclusion, what is the most complex problem you can undertake? I'd say it's starting a business.
What is a business? The word is so overused that we need to settle on a definition for this essay. I like Elon Musk's definition:
"All a company is, is a bunch of people together to create a product or service. There's no such thing as a business, just pursuit of a goal — a group of people pursuing a goal."
Now think about what it entails, to get a bunch of people to come together and work full-time to pursue a goal...