Though there are some aspects under the parents' control that contribute to their child's success or lack thereof, there is and always will be personal accountability in the child. Age is also a factor. If the child is nearing adulthood and is their teenage years, then it's more likely that the fault lays with the child rather than the parents (though there is still the possibility of the parents just not parenting properly). However, if the child is younger in age, it's more likely that they just need guidance from their parents. It's all highly variable on the child in question, the parents in question, and the surrounding circumstances, and any and all combinations of responsibility for the child's success can, will, and have happened.
Im a 17 yr old and i have to have a hair cut because they want me to be all military and me fucking up well that's my mistake that i have to learn and make sure that doesn't happen again. Children need to learn from there mistakes, parents shouldn't always come down there to do it for them its not fair we need to learn what we did wrong and correct our actions that's part of being human