When starting a company, most people shy away from truly hard problems and go for base hits thinking it will be easier. The opposite is true. Fewer people attempt the hard problems so there is less competition, and great people are more likely to join you on an impactful mission. Instead, start with something you feel in your bones must be possible or different in the world, even if it's not a business. Then work backwards from there toward what steps will be required, and see how you can get your first dollar of revenue on an early step which enables the broader vision.(Brian Armstrong)