[drfloob]

That depends on what you want to do with your life. If you want to build and sell startups, start building and selling them. You don't have to be a great developer to do that.

If you want to become the best developer you can be, then here's my advice:

Learn about the process of building software. Diligently practice various development systems (agile, scrum, kanban, etc.). Build a reliable, disciplined behaviour into your personal development process, so no matter what the task, you know exactly how to best take an idea through to completion efficiently and with as few headaches as possible.

After that: learn about architecture, algorithms, and hardware.