There are all sorts of co-founders, but the fundamental point is that, as a startup, you want to have all three, and the capital could come from bootstrapping but you should figure out advice and governance.
That is where I often see bootstrap companies fail in terms of really optimizing what they could be. They fall short because nobody is asking them certain questions that are typically asked. “How can you grow faster?”, “Do you have the right executives in place?”, “Is that incumbent entering the market a real threat or not?”