You are right, it is indeed hard work.That's true, but I'm just going from my experience where I'd practice it fairly consistently for over a couple of years, and I'd get pretty tepid results. But after a while of investigating my practice a lot and using a lot of trial and error and experiencing a crap load of doubt that made me want to quit a lot, I finally stumbled onto a technique that had consistently impressive results for me. I can imagine someone coming to it fresh faced and being a bit disappointed. It's best to find a competent meditation teacher, and also do a lot of investigation yourself. A lot of people think it's just like relaxing or whatever but it's way more active and a lot more work than most people think. It helps that the work is basically inherently enjoyable, but still.
I tried meditation for myself quite a few times but I can't get to the point where I'm fully with myself most of the time. But I have grown from what little I had of those successful meditation sessions.