Of course, project is important. Through the prophet Isaiah, God Himself says it proves He alone is God.
Isaiah 42:8 “I 
am the Lord, that 
is My name; And My glory I will not give to another, Nor My praise to carved images. 
9Behold, the former things have come to pass, And new things I declare; Before they spring forth I tell you of them.”
Isaiah 46:8 “Remember this, and show yourselves men; Recall to mind, O you transgressors. 
9 Remember the former things of old, For I 
am God, and 
there is no other;
 I am God, and 
there is none like Me, 
10 Declaring the end from the beginning, And from ancient times 
things that are not 
yet done, Saying, ‘My counsel shall stand, And I will do all My pleasure,’
What God says in those above passages forms the entire argument He makes throughout Isaiah 45, as well. People need to read that entire chapter, for in it God speaks of a coming pagan ruler named Cyrus, who had not yet been born (Isaiah 45:1-25)! Cyrus appeared 150 years later and fulfilled exactly what God had said he would. 
People who discount prophecy do so because they do not want to believe in God ... or, at least, in whom God says He is. After all, if there is a God, they could no longer continue to live the way they want.