The reason to make a new one is because there is meant to be an ecosystem.

Coins are not there for new people to find and mine, coins are there to trade for one another and support bitcoin.

NEW coins made (by you) are for you and your friends to mine, or for your school to mine, or for your team to mine, or for your WoW clan to mine, or whatever.
Then those coins are to be traded for other coins and used to support Bitcoin.