Why do humans suffer?

Because of our minds.

Beats the alternative

Human suffering is explained in the Bible with texts such as those found in ... nor do the intelligent always have the riches, nor do those with knowledge always ...

It is because of sin that we and others have brought into the world. The only hope is in Jesus Christ who takes away the sin of the world.

John 1:29

The next day John saw Jesus coming toward him, and said, “Behold! The Lamb of God who takes away the sin of the world!

Sin

The swift do not always win the race, nor do the mighty win the battle, nor do the wise always have the food, nor do the intelligent always have the riches, nor do those with knowledge always have success, because time and unexpected events overtake them all.”Ecclesiastes 9:11“Through one man sin entered into the world and death through sin, and so death spread to all men because they had all sinned—.”Romans 5:12

For this purpose the Son of God was made manifest, to break up the works of the Devil.”1 John 3:8“The whole world is lying in the power of the wicked one.”1 John 5:19