Is Radar Useless?

I'm a Master JG main. I almost never use radar (idk if thats the name in english). I always use wards cuz most games you need to ward the objectives all the time, trusting the teammates is bad, they will not ward. The only argument for radar is that it could make ganks easier in the early game, but I don't really gank early, I'm more of a passive jg that plays for mid-game and late-game. I play Evelynn kayle and lillia most of the time. Is radar really useless? I'm not using it correctly?