Considering these three together, it should be obvious that the greatest source of asymmetry lies in the area of listening, and the least lies in speaking. This explains, to some extent, the design style of so many products currently on the market. Most listen poorly and speak well. The typical product gives the user very little to say or do, and then hoses him down with megabytes of audiovisual extravaganza. Thus, despite my incessant carping about excessive speaking and insufficient listening, the current level of interactive design correctly reflects the asymmetric strengths of the computer.
Good design pursues the ideal while acknowledging the grain.
The ideal of good interactivity is equal emphasis on listening, thinking, and speaking. After all, the quality of a conversation is based on the extent to which each of the conversationalists listens, thinks, and speaks. If either person puts more emphasis on any one of these areas, then the conversation as a whole suffers. In the same way, participants in any interaction must focus equal energy on all three areas to do the best possible job. So we must compromise the ideal with the pragmatic reality.