The internet is the real world unlike school where you win a prize for finishing the race even if you came last. The real world is full of life lessons, if you write a post that is not factual, or that somebody disagrees with you will most likely get a down vote. The system is there to encourage you to write facts when it comes to technical stuff rather than blagging it with poppycock, and to encourage you to try to be nice. It also helps you to accept rejection, because in the real world there are some people that will down vote you for no reason other than they feel like it. Think about what you wrote and why people downvoted you, it will help you in the real world to get along.