I think this applies… But ONLY to software. The eternal term ‘vaporware’ is a large part of it. Not only that, most software authors don’t really design a true roadmap. Not to say they’re shooting from the hip, but it’s a much more flexible line of process than say a brick and mortar development. Software timelines seem to be more fluid, and that hurts a solid road map. The other option is to lock yourself in and in the best interest of following that map you aren’t able to include new items as they hit the market. New features, technologies, etc. Unless you want to stay a year behind the technology, like most large coporations do on say, computer hardware and infrastructure, you aren’t able to maintain a firm line. Again, it’s too fluid. There are too many ‘new’ things coming out too fast and to curb your staff and yourself you aren’t able to entertain new ideas or approaches.
I also think the ‘keep your competition guessing’ statement is a cop-out.