Why does God allow us to have tribulations?

One interpretation--we bring them on ourselves through our karma--

One can see tribulations as a gift to make us realize how dependent we are on God--(I'm expecting criticisms of this one--)

Answer

According to The Bible itself, God created man in his image. Not physically but mentally: He gave mankind the ability to choose rather than act on instinct like the other animals, the dubious gift of free will. Prior to consuming the fruit of the tree of knowledge, we were able to act freely without consequence because innocence was preserved so there was no suffering as a result of the choices made. However, once we chose to eat from that tree, we learned that everything we do has ramifications. Trials and tribulations are simply the result of people being able to make bad decisions. We all pay, communally, for the evils done by others.