God doesn't promise us health, wealth, success, or prosperity. On the contrary, the Bible tells us that trials are good for us.
(James 1:2-4 NIV) Consider it pure joy, my brothers, whenever you face trials of many kinds, {3} because you know that the testing of your faith develops perseverance. {4} Perseverance must finish its work so that you may be mature and complete, not lacking anything.
(1 Peter 1:6-7 NIV) In this you greatly rejoice, though now for a little while you may have had to suffer grief in all kinds of trials. {7} These have come so that your faith--of greater worth than gold, which perishes even though refined by fire--may be proved genuine and may result in praise, glory and honor when Jesus Christ is revealed.