Having a startup might sound sexy, but is a rocky road. You open your mind to absorb everything there is to know around your new idea. To shape it and to connect it right. This can quickly lead to a fully occupied brain - monkey brain -, lack of sleep.
Having a sort of purpose in live will make you more efficient, aligned and successful. It will be easier to make choices and you will be more committed to those. As a result its more likely you reach your goals and feel happier at the same time. Finding your purpose