While trying to keep control of a project or even your life, you need to yield to a cone of uncertainty.   What am I talking about, you ask?  As Hurricane Bill recently approached the United States, many would frequent news sites to view possible paths the hurricane might take.  The further into the future the path was predicted, the larger the cone of uncertainty became.  If you looked at the current date and time, you would see the beginning of the cone.  If you plotted it on a graph, it would be an exact x-y coordinate.   Now let’s leverage this analogy for the purpose of understanding Waterfall and Agile.

Waterfall

With waterfall (path A from the figure), you work and work and work, trying to refine your requirements documentation, your schedule, and your budget before the project even begins.  You do everything you can to lay it all out, attempting to account for every possible variable.  Unfortunately, you don’t know what tomorrow will bring.  So, the further out the schedule goes, the greater the risk something is going to change.  What’s it going to be?  Is scope going to creep or maybe the schedule will slip?  Whatever foreseen changes are ahead, there are going to be exponentially more unforeseen the further out the schedule goes.

Agile

With Agile (path B from the figure), you begin with the greatest unknown.  Just accept it!  You’re not the Amazing Kreskin.  You can’t predict the future.  The only thing that is guaranteed is something is going to change.  So, plan for that change.  Know the goal you’re trying to reach.  Keep your eye on that goal.  Now, do what you do.  Develop, lead, manage… it doesn’t matter.  What does matter is you see where you are right now, know where you want to go, and then at a measured time, see where you are again.  Make some adjustments and repeat.  You will find if you just accept the change, you can use it to your advantage to get closer and closer to your goal.

Summary

You can not predict the future, only plan for it.  You can not steer a hurricane, only plan for it.  You can not prevent change…  Can you guess what comes next?  That’s right, you plan for it.

People don’t plan to fail, they fail to plan.