A PM says to his senior manager, ” There is only a 50- 50 chance to deliver the project on time”. A reply like ‘”you take the risk and go ahead as it is ” would be a rare case especially in case of a project where on time delivery is a critical requirement. Back to the question from where we started, is this probability okay to proceed..?
Similarly, normally improvement initiatives triggered by the organization would lead to achieve the specification limits (range) of the PPO with a probability of 99.7 % ( or roughly>90 %, considering data variability in Prediction models) ie.to achieve above/below to central value of PPO, probability would be < 50 %. Now if the projects are targeting on the positive side (above to mean in case ‘ productivity’ is a PPO ), ultimately organization objectives could be attained. Otherwise reverse situation will happen. So project team would be targeting to achieve above to central value, in normal case. This means that probability of success is only 50 % even with organizational improvement initiatives.
Back to the question from where we started, is this probability okay to proceed..?
Certainly not, in the eyes of senior management. if a project is targeting for mean as PPO, then probably for success is 50 % only. So either there needs to be some other improvement initiatives inside the projects other than those triggered by the organization or the 50-50 risk of not meeting the target needs to be accepted by the senior management of the organization.
If additional improvement initiatives are triggered to make probability of success greater, definitely, the current mean would be changed, and in such a scenario project team needs to deduce the internal estimates with current mean.( see more on setting internal estimates)
Now there could be another case like, some of the projects are targeting below to mean due to certain genuine reasons. Then probability of success would be higher. But if the case is repeated among many projects, ultimately organizational objective wont be attained. So there needs to have mechanism to ensure that if any of the projects are targeting below to mean of PPO, there must have another project with PPO above to mean. Normally Engineering process group (EPG) needs to take care of this.