the round shape is the alignment, whether it is a disc, wheel, or ball / round shape.
as well as life,
blood, water, wind, all spinning.
live life is also like a wheel, there is happy sometimes sad, it is easy while others feel the difficulty.
someone who used to be rich is now poor, and vice versa.

in this world all of its looks rotates. starting from earth, moon and other pelanet. if it stops will kill the perish.
By the way,
money is also called currency, which is circulating, rotating, or distributing. if ignored its value does not increase, even shrink.

perhaps my writing is like, far away from the fire.
but your support is a great pride for me. thanks @xpilar