Why Allah created people knowing that some of them will end up in hell

What does it tell for the personality of Allah the fact that Allah created a human being knowing that the latter will end up in hell. Allah knew this fact, even before that human was brought to life. Therefore, my main question is this: Does this fact conflict with the fact that Allah's personality is described as merciful? Does it make sense in this case to discuss even for justice? Let me elaborate more on my question. If it is known before its birth that a person will not stay in paradise, simply means that that person will not have the capacity to understand God's Existence. It means that the person is not equipped with this capacity by the creator. Following the same logic flow, is it the person's fault that he is not provided with the faculty to understand? Apparently, the logical answer is no. Then, why does the person have to go to hell for smth that is beyond its control? Does even make sense to state that the person has free will?