Christians...
if we believe we have the answers (which we really do), then we have explanatory power...
If we have explanatory power, then why are we not using it?
One of the big problems is ignorance. Many "Christians" are not well versed, taught enough. They do not understand their faith completely.
Another problem is lack of faith. Some believes just do not believe that we have all the answers.
Maybe another problem is the lack of effort. Some Christians know that we have God on our side and know that we have the answers. They trust God and all, but they are not disciplined enough or serious enough about studying the Word of God and being ready at any moment to answer such questions.