I think you are hoping for a faulty philosophy.
A child who is difficult to train is no better at the subject than one who is naturally inclined to do things and is open to the process. The parent may feel a greater sense of accomplishment but that is their feeling and has nothing to do with the success of the child.
Someone who struggles to, say, play a musical instrument and overcomes it isn't a better musician than someone who has a natural talent for playing it. The natural musician will often be the better player because they have felt the connection and flow from the beginning.