Getting knocked out includes losing your job, your startup going bust, bad investment choices and a host of other possibilities. So you got knocked out, now get back up. Not everyone bothers to get back up, some people stay down forever...but this is not a bad thing since this helps distinguish the doers from the pretenders.
For those that do decide to get back up, it's a matter of how you do it and how long it takes you. It might be a personal thing and it might be a work thing. The best entrepreneurs get up quickly. They can take a hit and keep moving forward.