With a beginning shooter, there will inevitably be shooter errors. How do I know this? Because I am not a beginning shooter and I am still discovering shooter errors in myself. Even shooters who are far more advanced than I am get checked occasionally to identify errors that may have crept in unnoticed.
However, having bows that are designed poorly certainly doesn't help beginning shooters to progress, which is compounded by the fact that most beginning shooters have nothing to compare their current bows with, so don't know that a large part of their problem may be outside of their control.