If you don’t have the deadlines at your startup, you’re doing it wrong
When you’re working on your own startup, especially in the early days most of the time you’re the one who decides what the deadline is. And if you don’t, nothing is going to get done. Deadlines are wonderful in the sense that they focus the entire team’s efforts on a single task at hand.
Working on a startup means you decide your own schedule. That doesn’t come without the price though. If you’re sloppy and used to operate only under an external pressure, then you’ll be stuck in indecision and indolence.
So to be productive in a startup, set the deadlines, meet them. Have the consequences in the physical world if you don’t. Leverage the external deadlines such as those of startup accelerators or tech conferences  to your advantage. Apply the peer pressure and make sure to do at least one thing which improves your product every single day.
 Dennis and Naveen made mid-March of 2009 their deadline to launch Foursquare at SXSW.