When Calvinism (monergism) is contrasted with Arminianism (synergism), what first comes to mind is God’s role and man’s role in coming to faith. The Calvinist says that man plays no cooperative or contributive role in coming to faith, while the Arminian says that man cooperates with God in that man turns his heart to God, that is, exercises his will to come to faith. In Calvinism, God first regenerates the sinner and then gives the sinner the gift of faith, while in Arminianism, regeneration follows the sinner’s acceptance of God’s offer of salvation. Faith, for the Arminian is something the believer does, not something God gives, as Calvinism understands it.
Most Christians think Calvinism/monergism is a shtick: they’ve got the wrong end of the stick.