Why do good people suffer bad things?
We live in a world that was depraved and doesn’t know God. The bad things is from the devil and caused by the sins. So we need to preach the Gospel to more people and lead them to Jesus Christ.
Because God want people to know the price of the sins, so that the salvation could be meaningful.
God doesn’t want to see anyone suffers bad things. He is a loving God, people suffering is for the sins in the world. God has shown the salvation in Jesus Christ, and promised his people the eternal life, in heaven there will be no sins and no pain.
Who are good people in God’s sight? 
Because this is a sinful world, so people suffer including good people also. God does not want this, but acturely people suffer for their own sins or from others’ sins. Only Jesus is the way to save and makes people’s sufferings meaningful. Glory to God!
I like your answer. Actually, bad things are not from God. People’s suffering is because of their sin or others’ sin. Sometimes, God allows bad things happen to even his children to discipline them.
All the suffering are because of sins. Maybe ours or others.
Who is good, only God. But Christ also suffered. It is because of our sins.
Even good people suffered, God can turn it into good things.