Our Main Problem is our uncontrolled, dissatisfied mind, whose nature is suffering. This is primarily due to our unfulfilled expectations. We need to train our minds in order to see how due to our own ignorance and confusion we are hijacked into states of mind, thoughts, feelings, etc. that harm ourselves and others.
Meditation reveals everything that is in your mind; all your garbage, all your positivity; everything can be seen through meditation. You can direct this experience once trained, versus being continuously victimized by your mind.