Reynolds,
While Arminians and Calvinists both are motivated to preach the Gospel, it is the theological understanding of both groups that provides their motivation. Their respective theological understanding effects the manner in which the Gospel is presented. Even the content of the message may be different. Let me give you just one example.
Under the Arminian schema the pivotal character in the Gospel presentation is the sinner. Finneyism (named after the 19th century evangelist, Charles Finney) still is the majority position held by Arminians today when it comes to evangelism methods. The Gospel is presented and, to differing degrees, pressure is put on the sinner to make a decision. Whenever you see a church that plays multiple stanzas of "Just as I am" during an altar call, you are witnessing some form or Finneyism at work. Billy Sunday, Billy Graham and Jack Wyrtzen were Finneyistic evangelists (I used the past tense with Billy Graham because his days of public ministry are over due to his age and health).
Under the Reformed Calvinistic schema the pivotal character in the Gospel presentation is Jesus Christ. At its core the Gospel is the proclamation of the Word of God. Whenever the Word of God is proclaimed God is the central character. God is glorified regardless of whether a sinner is converted during a Gospel message. That does mean the Gospel is preached through dry rote. The Gospel still is the power of God unto salvation to everyone who believes (Romans 1:16). As such it should be preached in power and in truth. Very seldom will you see an altar call in Reformed Calvinistic churches. Why? Because the working of the Holy Spirit in calling sinners to repentance has nothing at all to do with playing on people's emotions. There is no need to give the Holy Spirit some extra time to work. You may see Finneyistic methods used in some neo-Calvinistic churches, but they are not in keeping with the Reformed understanding of biblical evangelism.
:thumbs::wavey::thumbs: