Representatives from the IT department of a major worldwide corporation came to Redmond and took time out of their busy schedule to give a talk on how their operations are set up. I was phenomenally impressed. These people know their stuff. Definitely a world-class operation.
One of the tidbits of information they shared with us is some numbers about the programs they have to support. Their operations division is responsible for 9,000 different install scripts for their employees around the world.
That was not a typo.
This highlighted for me the fact that backwards compatibility is crucial for adoption in the corporate world. Do the math. Suppose they could install, test and debug ten programs each business day, in my opinion, a very optimistic estimate. Even at that rate, it would take them three years to get through all their scripts.
This isn't a company that bought some software ten years ago and don't have the source code. They have the source code for all of their scripts. They have people who understand how the scripts work. They are not just on the ball; they are all over the ball. And even then, it would take them three years to go through and check (and possibly fix) each one.
Oh, did I mention that four hundred of those programs are 16-bit?