As human beings, we have learned to adapt to even the most odd and unordinary surroundings. Some people live in ghettos and others live in luxury. It is not hard to believe that the time when Christ returns will come unknowingly to the masses of people living at that time. The surroundings at that time will be considered "normal" to those living in it.
To overcome the way we look at our world every day, we must have a guide to live by which never changes. We see the world's moral/ethical scale changing every day. There is more and more violence at the movies and in reality. We see varying degrees of criminal and immoral activities on the evening news and we talk about it casually in our places of work. We are accepting as normal the practices of unmarried couples living together and pre-martial sex as common.
If we use the Bible as the scale to live by, perhaps we will notice that we are not doing quite as well as we thought. If we look at the Bible, we can see the moral decline, the increase in violence, and the acceptance of immoral practices which must precede the return of Christ. These things are all clearly foretold.