From the beginning of computing people have been trying to make computers do more and more difficult things. At first these things were difficult in the sense that people could do them but rather tediously and unreliably, like solving lots of simultaneous equations. Then they were things that for practical purposes people could not do at all, like the calculations of theoretical chemistry. Progress was made by:

Researchers were slightly surprised to find that, when they wanted computers to do things that people find relatively easy, progress was much more difficult. This should perhaps be rephrased a bit. After all, people do not pick up objects in a three-pronged steel gripper, and they do not translate from French to English starting with the text punched on cards. Nor do they see through television cameras or hear through microphones. It was hard to progress with problems that looked as if they were in all material respects like things that people can do fairly easily.