Idolatry occurs whenever we place anything in front of God. It is like worshipping the moon during an eclipse. Why would we want to worship the thing that is blocking the true source of light and life?
God wants to be the one we look to as the source of all we need, and when we look to Him for all things, we are truly worshipping Him. We commit idolatry whenever we look to anything or anyone other than God as the source of meaning or of things in our life.
God will do everything He can to bust us of the idols in our life. People think of idols as things people would make or carve, and then bow down to. We need to broaden our understanding of idolatry. Just like the eclipse, it always obscures our ability to see God and to receive the blessings of His light.