No one wants their child to fail. Over protective parents, therefore, tend to heavily guide a child's results or "model" success. But a child can learn a lot when the work is their own, the consequences are minor, and you're there to pick up the pieces and encourage them to try again.
Moments of failure produce resiliency. It is the tougher-than-nails ability to sort out the bad feelings and face the future with new-found energy and zeal. Better to learn how to do this in elementary school when the consequences are minimal, and before kids leave the nest and try to make their way on their own. The downside of not allowing kids these learning opportunities early is that fear of failure becomes their modus operandi, causing them to avoid risk at all costs and stifle their own creativity. Instead, young children should develop confidence in their ability to navigate their way to success and view any hiccups as "an opportunity to find new ways to reach the goal".
It seems counterintuitive to want your child to fail. Instead. you can welcome these "learning moments" and call them opportunities for growth instead.