Why is Evangelism so difficult for so many?

One of the questions I’m contemplating today is, why is evangelism so difficult? Sharing our faith with others so difficult. I am coming to see that the presence of an evangelistic spirit is a sign that a Christian’s primary allegiance is to Christ, that is, their love for Christ has permeated their entire life. Evangelistic people have one primary allegiance in all they do: their faith shines forth whether they are at the store, or in school, or at work or at home. Their primary allegiance to Christ is a value that colors everything they do or say. It isn’t something they have to do, rather it is more of who they are. This isn’t true of every Christian. Perhaps this is because Western society has divided our culture into private and public spheres. For most Americans, religion is often considered a private matter. So what governs the public side of life?
On the mission field, missionaries often discover that new Christians have dual allegiances. What this means is that new converts have changed their allegiance to Christ, but they retain previous allegiances to traditional values or power sources. So they might go to church on Sunday, but they also visit the medicine man when their child gets sick on Thursday. They do this because they haven’t come to that the medicine man is sort of a false Christ. Hopefully, this will change in time. If one applies this model to the USA, could it be that where an evangelistic spirit is lacking, people as are maintaining a dual allegiance? To put it another way, a person with a dual allegiance demonstrates faith in their private, religious expressions, but really hasn’t let it take hold in the other area of their lives. They reveal their allegiance to Christ inside the buildings specifically designated for religious purposes (Churches); but outside these buildings, they allegiances are to secular values, many of which are good such as helping others, volunteering, hospitality, but which are kept separate from a religion or a religiosity. Sickness is a medical problem, and doesn’t really concern God unless medicine has failed. Finances are the result of personal decisions and wise or unwise choices, and are not considered gifts from God judging from American’s behaviors and attitudes. Americans also value education based upon human knowledge, yet education about religious knowledge is hardly attended or almost never funded. Could this be a sign of dual allegiance, a secular allegiance to science and technology, and a religious allegiance to Christ? If this is true, such insight might help explain why evangelism is so much work for so many Christians; they haven’t recognized that they are maintaining dual allegiances. Something to think about.