"Landmarks events don't occur very often in life, and as advancements in technology come and go, the landmark evens come less frequently. Consider the area of transportation. For centuries, we relied on the brute force approach, while in the last 125 years we have gone from horse-drawn carriages to steam powered and gas powered engines, on to flight and eventually to space travel. The last major landmark is now more than 30 years in the past, and it's difficult to say what will happen next. "