Hijacked by Assumptions

That was the phrase at work today. Many hours of team effort disappeared down a plughole. We make quite reasonable assumptions and they lead you down a path so long that by the time you realise you're well and truly lost you've forgotten what those assumptions were in the first place. And, of course, when you eventually trace the path back they inevitably prove to be false. I guess that's true in life every bit as much as it is in software development.