I’m not a huge fan of over-planning things. One my all time favorite quote is Mike Tyson’s “everyone has a plan until they get hit”. Tyson’s own stupidity aside he makes a good point. There is a perpetual myth in business that planning something to the finest detail will avoid problems. The truth is nobody can predict what will happen 6 weeks out, never-mind 6 months out.
In any project or plan there is the tendency to underestimate the time it’ll take to get things done. Humans are tainted with a general laziness that tends to leave everything till the last minute. Especially tasks that are not very interesting.
This quote from Wikipedia sums it up…
In one study, 37 students were asked to estimate the completion times for their senior theses. The average estimate was 33.9 days. Only about 30% of the students were able to complete their thesis in the amount of time they predicted, and the average actual completion time was 55.5 days
In web design it’s better to plan in short spurts. Plan for a week or two ahead and then review the plan at the end of each period. In Agile methodology those periods are called sprints. In our office we call them common sense. Setting realistic attainable goals keeps everyone both focused and in a mild state of urgency.
It’s still possible to plan far ahead but don’t get married to those milestones. Rather be prepared to adjust quickly and decisively when things don’t do as planned. It’s better to have an A+ team with a good-enough-B-plan that’s well trained to deal with obstacles than a team of B players with a A+ plan.