If there's a particular drum I bang over and over again, it's the "keep it simple, stupid" drum. This term has almost become a cliché , but hey, "if the shoe fits, wear it". (Oh sorry, that was bad...just couldn't help myself ;-)
Anyway, when I was doing project work, I was always the guy advocating for people to "take it slow", "do things in stages", "no big bangs", "Amazon wasn't built in a day", etc., etc. I believe that quick, iterative steps yield better results, less bugs and get you to the end goal faster than big, monumental projects. The problem, it seems, is that companies like to have big, monumental projects. The bigger the company, the more monumental the projects seem to be. I think this is dead wrong. It's not the way our brains work, it's not the way people are most efficient and looking at the abysmal failure of so many IT projects, it sure doesn't seem to be the way to run a business. So why do we keep doing it? I guess if I knew the answer, I'd be running a shop somewhere instead of pushing software. :-)
In my "To Read" stack of magazines, I recently came across a jewel of an article in the April 2008 issue of Baseline. The cover story in this issue was a piece outlining the failure and eventual redemption of Symantec's new ERP implementation. A classic "big, monumental project", it was undertaken without really understanding the needs of the very people that would be using it. As they found out, such an oversight almost completely crippled their business. In the end, what saved them was a new project that put the focus on the user experience.
I don't want to rehash the article here...I highly recommend you go and read it...but I do want to point it out as a prime example of a project gone wrong because the final end goal wasn't made clear. That final end goal always has to answer the question "Who is going to be using this and how will this project help them do their job". If you're not asking this question and getting the answer in your project, then you are doing your users a disservice. Keep their goals in the forefront...that's why you're there.