When it comes to business owners, rationality is overrated. I've seen a lot of companies that are perfectly happy hiring a less competent dev that accepts 20% less, and takes more than twice the time to do the work.
There certainly are plenty of companies out there like that. I tend to think that generalizing like that is dicey, though. The good, well-managed companies out there tend to keep the same developers for a long time, and any that leave tend to not have many complaints. The poorly managed companies tend to churn through lots and lots of developers, many of whom will go on to write blog and forum posts on how irrational and cutthroat business is. Thus the noise about poor management is louder than the reality.
To the accounting department it is perfectly rational. In the accounting department everybody is an identical square in the spreadsheet.
In the spreadsheet, if square "A23" takes n hours to accomplish a task, the spreadsheet tells them they saved n x 0.2. This means that the longer it takes square "A23" to accomplish a task, the more the company appears to "save" in the spreadsheet.
