As for me, it was a chance to try myself in a small but very inspired team with different tasks, deadlines and ideas. You can try, try and once again try different approaches. It boosts your skills and experience in a wide range of activities.
For me the answer is pretty simple: it is a project that started in my heart! I am building something that I genuinely believe in, and it is almost part of my DNA. It doesn’t mean that I didn’t believe in the things I created in the past. However, none of my past products were so close to representing my beliefs. That's big reason why I started my second startup, working on the product that started in my head allows me to express myself by my work. Obviously with people joining the team it will become collective vision, however there is part of me in this business. It's much harder to impact the outcome by working for already established big organization.
What are the tradeoffs between going to a startup versus joining a mature company? Having done both, several times, I get this question all the time. There are many things to consider and lots of “it depends” when it comes to where you are in your career, where you live, and many other factors. Here’s my perspective on the tradeoffs.
The smaller the company the more impact each member of the team makes. More responsibilities, more opportunities to learn, to grow professionaly, and to jump start your career. More freedom, and more reward! Teams are close-knit groups that hang out together after work. Not to mention dynamic environment and being a part of a cool disruptive technology.