The image here is of a potter, busy with her creations which she stores up for future use. Some of the pots are well-made and beautiful, others may be flawed and clumsy.
This is the symbol for our activity in the world, which is known as karma (Sanskrit) or kamma (Pali.) The word means "action," more specifically "effective action" or "work." This action arises from our ignorance. Because we do not understand things in their true nature, we are endlessly taking action in the world. Because of desire, which is rooted in ignorance, we seek always to modify the universe to our liking.
This modifying action inevitably creates an imbalance and the universe does not tolerate imbalance on any level. For every action, there inevitably follows an equal reaction. We reap what we sow.
All our experiences in the world are the results of karma which we have been accumulating since beginingless time. Beings can be compared to chaff on the wind, blown from birth to birth endlessly. But the wind is karma, and is of our own creation.