In reality, upgrades represent the effort of software companies to track the changing interests, values and needs of both the existing and future customer. The cost of upgrades is another fascinating aspect of this story. Upgrades represent a new paradigm for buyers. The same tool remained equally productive in the 20th year on the job. Now fast forward to today.
Typewriters are largely irrelevant.
The new tool of choice is the PC-based word processor. You can almost budget from the day of purchase the date when you will consider replacing or updating your software. Reluctant technology users often see computers as a treadmill, an endless process of software changes followed by the requisite hardware upgrades. It is for this reason, as much as any other, that I encourage my clients to make the effort to budget technology thoughtfully. Examples include AutoCAD, Quickbooks, and Windows.