There are factors that can attribute to someone going through Hardships and Sufferings. Life in general is unfair. Coupled with the fact that we live in a wicked world where some people's joy is in another's man's pain. While there are times when God would avert such situations from arising, there are also times He may allow them to happen and they are for good reasons.
The bible tells us that I'm every situation—be it good or bad—we should give thanks to God. The perspective of God and the perspective of man is not the same. This is why God needs us to trust Him. If we are waiting for God to show us preview of how the entire journey would be we may never really know how to cultivate genuine faith in Him.
This is why faith comes to play. When God is having dealings with us we can be rest assured that it is all for good. God said it Himself that He won't let any yoke that is greater than us come upon us. God's dealings does not break us but make us. He will never leave us halfway of the journey but stay with us till the end.
Romans 8:18
For I reckon that the sufferings of this present time are not worthy to be compared with the glory which shall be revealed in us
The glory that awaits us when we have passed through all these phases in life is nothing compared to the glory that awaits us. The bible also made a reference to a woman in labor who after giving birth does not even remember the pain she went through anymore. That is how it is when we shall come into God's rest