Sources: Electronista, ZDNet
quote: B) For that same reason, implementing backwards compatibility is a TON of work. For every feature you want to make backwards compatible, you have to do twice the design, coding, and testing, or more (i.e. design feature x for new system, design feature x to work the same way in old system. Build feature x in new system, build feature x to work the same way in old system. Test feature x in new system, test feature x in old system, etc.).