I recently put together a brief Prezi presentation on Waterfall vs Agile.
In doing so, I had to really think about why exactly I think waterfall is bad.
The feedback loop
It really came back to one central thing for me, which is the length of the feedback loop. When we are using a waterfall process for software development, the customer doesn't really have a chance for feedback until the end of the project. Even the testing is done at the end of the project, so that feedback is coming very late.
The biggest strength Agile gives over Waterfall, is the tightening of that feedback loop. The quicker you can get the feedback, the quicker you can respond to it and the less time you spend going in the wrong direction.
From a programmer's perspective, think about how many of us used to write code before the tools came along to help us, and before we knew any better.
Write a bunch of code for 2 hours
- Run the compiler
- Fix an error
- Recompile
- Repeat 2-3 until all errors are fixed
That wasted a large amount of time. Especially when we had some syntax wrong that affected large portions of code.
Using a modern IDE, we are able to see syntax errors getting highlighted the second we type them. We can start to type a method name and auto-complete can take over and offer us suggestions. It it difficult to write bad syntax because we are getting constant and immediate feedback as we write out code. The feedback loop is so tight that we don't even consider compiling to be a separate step. There are even some IDE plugins which will continuously run any unit tests which may be affected by your code change in the background as you are making the change.
If the modern IDE experience is Agile, then Waterfall is punch cards.
Taking the best of all
So, here is my prezi presentation. Please give feedback if you have some. Remember this presentation is designed to be a very basic beginner's guide to why someone should choose Agile over Waterfall. It is not going to go into very detailed topics about Agile.
Also, at the end of the presentation you will notice that I suggest taking some of the process of Scrum, and the XP best practices, and running Kanban using those guiding principles. I currently believe that is the best mix of what Agile has to offer.