Gotta remember not everyone is wired the same way or responds to stimuli the same way.
Some sounds work great for sleeping, while others not so much. It might sound paradoxical, but silence also has a noise to it. For me, the noise of silence is hit or miss for sleeping, white noise is too sharp and annoying, and nature sounds are often a bit too distracting. What I've found works best for me is rounded brown noise.