I think that Dota 2 is a better game than league of legends due to what i have heard mainly, bigger prize pools and competitive scence. The graphics also seem better and LoL is said to be much easier and not as challenging. However i have not played LoL so cannot confirm these myself.
You've never even played League, so your argument is already invalid. You can't say Dota 2 is better than LoL if you haven't played it. Don't judge games off of rumors you've heard from ignorant kids on the internet. Evermore, graphics don't mean sh*t (take Minecraft for example).