Posted 04 May 2007 - 07:09 PM
I no longer work for Motortronics, but I was around when a lot of this was happening and I concur with GGOSS that it has become very commonplace with manufactures of digital electronics. From my experience there are several problems that cause this;
1) They find new special case situations where some feature they have does not work correctly in some specific situation, so they make a correction and decide they had better incorporate that into all future products to avoid that issue in the future. You could make the argument that they should only make that correction for the special case they find it in, but try to justify that to the 2nd person who runs into it.
2) Similarly, some customer suggests that they add a new feature to get a big order, or they insist on a feature previously found only in a competitor's product. To do the engineering once is enough, so they add it in for all future products.
3) There is a surprisingly short life cycle on a lot of components and digital products now, meaning that all of a sudden, working systems must be changed to accommodate a replacement device, which often works slightly differently than before. This usually necessitates a new firmware and or software change as well and is the usual reason why backwards compatibility is usually impossible.
4) Long term failures of component parts. As a system matures, like the MVC3 controller, they find that some small component is beginning to fail too early. A classic for Motortronics during my tenure was DC/DC converters used in their PC board level power supplies. They went through almost every supplier in the universe before they finally gave up on finding a reliable one and started making their own from scratch. Every time they went to a new one, it worked ever so slightly differently and needed new firmware to accommodate its idiosyncrasies. It was maddening for quite a while on that issue; one brand worked like we wanted it to, but couldn't stand the elevated heat. Another lived in the heat but required repeated tweaking of the crowbar circuit for orderly shutdown on power loss. Then it started failing from voltage spikes so we switched again, and again, and again. Each time, the new firmware made the new software versions incompatible with old hardware.
"He's not dead, he's just pinin' for the fjords!"