This quote from the article sums it up nicely, especially if you consider that software was once finished, printed out, and then reviewed by a team in a boardroom, looking for bugs:
Consider the game “Where’s Waldo,” in which a cartoon character is hidden in an intricate design. Most people can eventually find Waldo after poring over the drawing. Similarly, when programmers check code for errors, it takes time to examine the logic and find mistakes.Now imagine if someone sat next to the artist from the very beginning. Obviously, the onlooker should be able to find Waldo more easily. The character would stand out.