Some people do not become Christians, and if God knows what people are going to choose regarding their salvation, why does he let them choose hell? How is that fair? Especially since God loves them. Doesn’t that contradict the plan that God has for humankind? How could that make God not be a failure, allowing people to go to hell.”
This is a classic question, and you are not the first to propose it. The answer is two-fold, one from God’s view, and one from man’s view. However, let me first say that the only place God has revealed Himself specifically is in His Word. Of course, His creation in general declares His glory; but, it is only enough to convict man. Paul tells us that in Romans 1:18-21: “For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who suppress the truth in unrighteousness, because that which is known about God is evident within them; for God made it evident to them. For since the creation of the world His invisible attributes, His eternal power and divine nature, have been clearly seen, being understood through what has been made, so that they are without excuse. For even though they knew God, they did not honor Him as God, or give thanks; but they became futile in their speculations, and their foolish heart was darkened.” Notice in this passage that God made sure everyone knows He exists “within them” so they are “without excuse.” Even so “they knew God but they did not honor Him.” This is critical to your question.
Thus, the Bible is the only source of information to getting the correct answer. The Bible is not the thinking of a few godly men. It is an accurate recording of God’s Living Words to mankind. Like it or not, we must bring our thinking in line with what the Bible says; not the other way around. A couple of passages will help us realize how God intends for us to view the Scripture. “But know this first of all, that no prophecy of Scripture is a matter of one’s own interpretation, for no prophecy was ever made by an act of human will, but men moved by the Holy Spirit spoke from God” (2 Peter 1:20- 21). “All Scripture is inspired by God and profitable for teaching, for reproof, for correction, for training in righteousness” (2 Tim. 3:16).
Let’s look at what God has revealed to us about Himself. He is sovereign (He answers to nothing and no one for His actions). He is omnipotent, all-powerful (He acts as He pleases without any resistance). He is all-wise (He knows every possible thing and only chooses to do the most excellent thing in every instance). He is omniscient, all-knowing (He is aware of everything always). He is omnipresent (everywhere at all times). He is loving (nothing He ever does is less than the most loving thing to do). He is Holy (there is no evil in God and He is incapable of doing evil). He is self-existent (He always was, without beginning or end). There is much more, as we will see below.
“Fair” is a human term. It does not—it cannot—apply to God. Both Job and Paul discuss it. When Job was going to question God about why he was experiencing tremendous hardship, God answers with a question: “Who is this that darkens counsel by words without knowledge? Now gird up your loins like a man, And I will ask you, and you instruct Me. Where were you when I laid the foundation of the earth? Tell me, if you have understanding” (Job 38:2-4). God asks Job why he is trying to tell Him about something he knows nothing about. The entire plan of God was laid down at the foundation of the world, and no one was present at the time. Similarly, Paul says the same thing in Romans 9:20-21—”On the contrary, who are you, O man, who answers back to God? The thing molded will not say to the molder, ‘Why did you make me like this,’ will it? Or does not the potter have a right over the clay, to make from the same lump one vessel for honorable use, and another for common use?” A sovereign God does as He pleases; a Holy God can only do good; a wise God only acts in a perfect way. He cannot make a mistake; He cannot fail.
It is true that God knew (in fact, actually permits to happen) everything about His creation before it came into being. Thus, He does indeed know everyone who will believe or not believe in Him. But that does not make Him responsible for someone not believing. Paul expands this point in the Romans 9 passage we already looked at above. In verses 14-16 we learn that no one deserves anything. God could just have created mankind and then, when we die, just allowed us to cease to exist. The fact that we get to live, and know there is a God, is far more than we ever deserved. We deserve nothing. Beyond that, if God chooses to save some, it is completely at His pleasure. “What shall we say then? There is no injustice with God, is there? May it never be. For He says to Moses, ‘I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion.’ So then it does not depend on the man who wills or the man who runs, but on God who has mercy.” He allows all to see His Glory, which the presence of evil actually magnifies. We are told this in verses 22-24 of the same chapter: “What if God, although willing to demonstrate His wrath and to make His power known, endured with much patience vessels of wrath prepared for destruction? And He did so in order that He might make known the riches of His glory upon vessels of mercy, which He prepared beforehand for glory, even us, whom He also called, not from among Jews only, but also from among Gentiles.”
You commented that if people go to hell then God failed in His plan. But, that assumes that God’s plan was to save everyone. In fact, if that was God’s plan, then He failed just allowing sin to enter the world to begin with; because, before sin everyone was going to heaven. Since He is sovereign and all-powerful, He could just have created the world without the possibility of sin. Since God does not make mistakes, then whatever happens is, in fact, God’s plan. And it is perfect. This makes sense knowing what we do about God. He is self-existent, so He always existed in perfect, satisfying, harmony within the Godhead. Father, Son, and Spirit eternally fulfilled within themselves. They lacked nothing, since God is infinite. Therefore, the only reason that God would “decide” to create the universe is to give something to the creation. Nothing can be added to Him, since He is eternally perfect. Time is a created dimension, along with space. Time is not something that limits God, or even something within which He must work. When He “decided” to create, He instantly knew everything that would happen. How could He fail in a plan that He created and instantly knew every part of? He would just have changed whatever would fail to what would succeed, and create that. This is why I said that “failure” is a human concept which is totally foreign to God.
Not only that, but it is also the most loving thing to do. God is Love. An important thing to remember about the Person of God is that He cannot stop being one attribute while He is demonstrating another. By that I mean that He cannot be doing the wisest thing while not also being Holy, Loving, Powerful, Righteous, Just. He is everything always. As humans, we can be loving at times and mean at others. God, on the other hand, cannot ever stop being loving, even while He is demonstrating His wrath or justice. God cannot ever be unloving, no matter what He does. It isn’t unloving to sentence a convicted criminal to the punishment he legally deserves. Thus, God is loving while being Just.
Now let’s look at the answer from man’s view. We are made in God’s image as revealed in Genesis 1:26. One of the key characteristics that was imparted to us is the ability to choose. Angels are created beings with some special capabilities, but they cannot choose and do not have the ability to desire. They are faithful in service to either God or Satan. This is the great plan of God. Humans can desire to know God and choose to believe in Him. They do so uncoerced and in so doing give God love. No other creature can do this. Angels cannot be saved. They look in wonder at salvation—”It was revealed to them that they were not serving themselves, but you, in these things which now have been announced to you through those who preached the gospel to you by the Holy Spirit sent from heaven—things into which angels long to look” (1 Peter 1:12).
No human being is ever made to believe. No human being is ever restrained from believing. If someone dies without believing in Christ it was exactly want they desired to do. We know that we only do what we want to do. We are not robots. Now we can see the importance of Paul’s statement that God placed within every human the knowledge that He exists. No one can ever claim they never knew. The famous promise of the gospel in John 3:16-18 makes more sense knowing this—”For God so loved the world, that He gave His only begotten Son, that whoever believes in Him should not perish, but have eternal life. For God did not send the Son into the world to judge the world, but that the world should be saved through Him. He who believes in Him is not judged; he who does not believe has been judged already, because he has not believed in the name of the only begotten Son of God.” Notice that God does not condemn anyone to hell. If a human, who was created with the knowledge that God exists, decides not to believe, he has condemned him or her self. Thus, as it pleases God, He gives a gift of salvation to those who believe; while, those who do not believe have condemned themselves to an eternity without a relationship with Him (yet with the sure knowledge that He exists permanently within). This is the eternal agony of hell—spiritual thirst within sight, but not reach, of quenching. Ever knowing the truth of His existence; yet, without ever being able to enjoy Him. In this life we believe in God by faith. In eternity, every human will believe in God because each one will have looked directly into His eyes, standing in front of Him, and heard His voice with their own ears pronounce their future—”Then I saw a great white throne and him who was seated on it. Earth and sky fled from his presence, and there was no place for them. And I saw the dead, great and small, standing before the throne, and books were opened. Another book was opened, which is the book of life. The dead were judged according to what they had done as recorded in the books....If anyone’s name was not found written in the book of life, he was thrown into the lake of fire” (Rev. 20:11-15).
Just because we, as created and imperfect humans, cannot understand how both parts of this Biblical answer mesh, it does not mean they are not true. There is a lot we do not understand. We are only expected to act on what we do know. We know we have the ability to choose what we desire. Matthew’s gospel promises, “Ask, and it shall be given to you; seek, and you shall find; knock, and it shall be opened to you. For everyone who asks receives, and he who seeks finds, and to him who knocks it shall be opened” (Matt. 7:7-8). It is the single most important choice we make in life.