In my first draft of this article, the opening sentence was "Planning is dangerous". But I decided to change it, as I do not want to sound like I am completely against planning.
Planning is good. It is definitely needed for healthy work. You certainly benefit from having a rough direction and a plan of how to get there, listing more or less the steps required along the way. Please notice I used “rough direction”. The reason behind this is that planning is dangerous.
The problem with plans is that they are solid positions anchored in the past. Though people tend to think the other way around. They think, for instance, that they are planning five years into the future, but in fact no-one has developed the powers to foresee the future as of yet.
When a plan is created, it represents a very limited vision of the future as seen from a certain point in time. As we progress along the timeline, this limited view of the future is a frozen picture from the past – it is a solid position from those old-and-forsaken days. The plan becomes a view from the past, not the future.
Things change and they change quickly. Staying attached to a plan that represents ideas from six months or one year ago, means that you are looking back, instead of looking forward as you definitely should.
Some argue that plans are living things. It is certainly true and, the longer the plan, the more of a living thing it will be. A one-day plan will hardly change (even though it might). A one-week plan will certainly change a bit, while a one-month plan is probably quite useless after the 10th day. The longer the plan tries to reach, the more useless it becomes. That is why most of the time planning feels like guessing. It should even be called so, according to Jason Fried and David Heinemeir Hansson.
Even a supposedly safe one-day plan may fall onto this guessing category. You plan - or guess - that you will be able to take part in all the meetings set up for the day, but a family emergency might force you to step away from your initial plan/guess. The family issue represents the present, while your initial plan from the morning was just rough guess work of what would eventually happen along that day.
It is no surprise that the software development industry has quickly adopted tools like Scrum with its one-iteration plans. Longer than one-iteration plans are supposed to work only as very rough guidelines. What matters is the average two-week period that an iteration takes. Things change so quickly that trying to see too far into the future is futile. In some software projects even the two-week iteration buffer generated by Scrum may not be enough. This might still be a too long of a plan/guess. That's why some teams have started to experiment with Kanban.
Both, Kanban and Scrum, do not ditch planning, as some people mistakenly believe. They simply put planning under the correct perspective. They realize that long term planning is dangerous and they keep the team guesses on the now instead of on the past.