Several months ago Mary Poppendieck visited Krakow, where I live, to give a speech. Mary delivered one of her standard pieces on lean software development, which wasn’t really an epiphany for me. However one thing sticks with me until today, so after all it looks like Mary did pretty good job.
It was about backlog size and Mary’s point was it should be as small as possible, but of course not smaller than it still makes sense. I can’t recall the exact example now but it was like you should have about the same number of items in backlog as you have in ready-ready or todo stage. In terms of our Kanban board it would be like maximum of 3 features in backlog.
The reasoning was that keeping big backlog effectively means you may have huge lead time (a time elapsed from putting the card on the board to moving it to done-done stage) which is an obvious case of waste. As we all know waste is bad so we should have possibly few items in backlog.
Now, the reason I still have this part of the presentation in the back of my head is I completely disagree with that. Well, I won’t say the bigger the backlog is the better, but I’m against setting up a goal of having tiny backlog.
Actually backlog is like Santa Claus bag for me. It can contain millions presents and still looks pretty handy. The cost of adding an item to the backlog is very low. How much time you could have wasted while writing several word on a sticky note?
Where’s the trick then? If you add too many items to backlog it will become clutter and product owner have tough time dealing with it and making good decisions what to do next. And clutter is like waste. And that proves Mary’s point.
But it is still product owner’s decision either to throw something away or keep it on board.
There is of course a plus side too. Make it easy to add things to backlog and you will have a container for all features you forgot during initial development or those you should build as soon as there is a free developer. You will have a reminder which functions were omitted and which important changes you discussed on design meeting a couple of months ago. You will have a better understanding of the product’s current shape.
Decision what to do next made by product owner may be more difficult but it will likely be better.
If you ask me this is fair trade-off. I choose flexibility over making decisions easier. And I definitely don’t call content of our backlog a waste. Well, I don’t, unless sticky notes fall down from the board and cleaning lady throw them into the bin.
By the way I hope to start this discussion with Mary at AgileEE where we both have presentations. Do consider visiting Kyiv in October. This is going to be great conference.
And how big is your backlog?Advertisement: Help to create Study on the Image of the Project Management Profession. Complete the survey. The survey is run by my fellow blogger – Ciprian Rusen from Corporate Geek.