Critical Chain Project ManagementAlmost all projects fail in terms of time and cost, but this is not because we do not plan carefully enough, but rather because we plan to fail. The main reasons for incorrect planning are:1. We plan under the assumption that our project won't change its scope, but it always does. You will never find a project where the scope has never changed during the project phase. At best, the change has been slight, but typically the changes are significant enough to impact the project. The question is: if we know the plan will change, why do we plan assuming it won't change? Tasks finish after the deadline or, in the best case, on the last day: a project is made up of tasks and the probability of tasks finishing before the deadline is zero, which means that the probability of a project finishing by or before the deadline is zero. This is due to 2 main factors: a. Student Syndrome: As students do, if I know I have enough time I will start my tasks after the project starts (i.e. if I have 10 days to do a task but I know I can do it in 5 days, I will probably start on day 3, 4 or 5, which means I will eliminate the safety stock from my tasks and could, at best, finish that task on the last day (if nothing happens)b slower: when you look at how people progress through the their project: They usually get to 80% completion of a task very quickly but take much longer for the last mile. When people start early and get to 80% quickly, they tend to relax or if they know they could finish early, spend more time than necessary improving details that are not really necessary or simply wait until the last day to finish their tasks. Furthermore, people do not tend to finish ahead of schedule because when the times for tasks are negotiated, managers push for less time and employees have a safety supply because they don't want to be punished for being late. If they happen to finish a task earlier than expected, it would give their managers the message that they could have finished earlier and that they will not receive extra time in the next negotiation.” Even though you might think “this won't happen to me and my project”, you should look at the facts.