A lot of players can aim at the notes correctly, but due to a high OD it can make it difficult to hit accurately. If you genuinely feel like you cannot improve no matter how much you play, you may be playing maps that are too hard. Like all games, your progression should be steady, and this means trying maps dedicated to patterns you are having problems with.
Also make sure you're checking the comments on beatmaps with a low average rating. If a lot of them point out something negative (and not sarcastically) you should play another map.
Finally, if you play one map too often you might "mindlock" it meaning you will mostly/always mess up at one certain part. Play a diversity of maps around your skill level; it will help you.