In D&C 8, the Lord gives Oliver Cowdery the power to translate the Gold Plates. The Lord directs him four separate times in verses 1, 9, 10 and 11 to ask Him for the translation he needs. In D&C 9, we find out that Oliver was perfectly obedient to these directions to ask, yet he failed and is chastened by the Lord because he did not “study it out in his mind”. Why would the Lord tell him four times in section 8 to ask, and yet say nothing about studying it out in his mind?
The answer to your question is found in Section 9:
5 And, behold, it is because that you did not continue as you commenced, when you began to translate, that I have taken away this privilege from you.
Now it seems very likely that before Oliver Cowdery asked for permission, he did ponder it and study it. When he asked, the Lord gave him the missing pieces; permission and instructions to ask in faith.
Apparently Oliver, like many of us focused on the new stuff and neglected the actions and behaviors that got him there in the first place. This can be an all too common failing.
Of course God, being God, knew that this would happen, so why didn’t He intervene to correct it? That is simply another form of the question of ‘Why does God not stop bad things from happening?’ We simply have to have faith that God knows what He is doing, and what He is doing is for the best.
That leaves us with speculation. In this case I would speculate that God did not need Oliver to translate (Joseph was called for that), but he did need to teach Oliver how to receive answers from God. Now, God is a master teacher, and I know that sometimes I learn the most from my failures, and not necessarily as much from my successes. Maybe that is what Oliver needed in order to to learn?
Also Oliver was a School Master by trade who shouldn’t have needed to be advised that some measure of intellectual rigor would be necessary to undertake the work of translation. Hence the absence of any “study-it-out-in-your-mind” injunction in D&C 8. It’s what I perceive to be a general, gentle tone of “you-should-have-known-better.” In D&C 9 it becomes clear that whatever process Oliver used lacked any real intellectual effort on his part.
I do know that because of Oliver’s request and struggles we have Doctrine and Covenants sections 8 and 9. This allows all of us who read and ponder the words and instructions to also learn the lessons that God was teaching Oliver. How many hundreds or thousands of people have also been taught because of these events? While my thoughts are speculative it is not really that hard for me to think of some very good reasons that God might have had to let this happen.
Anyway, for those interested, the Church has posted an article covering the events in question here. You can read here.