PvP is all about power. They will put you with a over powered guy who can defeat you easily. Even if you become more powerful than now you will get more powerful opponents than you. And those powerful guys will reach leaderboard. Actually you will not play for you. You will help them to reach top positions. But you can invest some money if you want to be like those powerful guys. Or just be happy with story mode(which is Amazing) and uninstall after completion or get frustration by playing PvP.