Bottom-up versus Top Down Scheduling: When and why?

Schedules are important. Every project and program must have a detailed bottom-up schedule for tracking purposes that has been created by firstly gathering and understanding requirements and then determining other areas of scope such as WBS, inclusions, exclusions, deliverables, constraints, business objectives, assumptions, high level timeline, etc. Effectively outlining what needs to be delivered to meet requirements so you can then estimate the effort required for the work/tasks and create a timeline or schedule. Something to this effect and apologize if I missed anything and its simplicity. Main points to come.

However, in many organizations I have worked for, normally only funded projects with dedicated trained Project Managers or a Scheduler produce track-able schedules or even know how to create one.

So how can you start performance tracking all the projects in your organization or department once you know them (i.e. your entire strategic and operational project portfolio) if most of them don't even have a baseline schedule?

Starting Point - Ask each Project/Program Manager to supply you the following:

a) Their project(s) original and/or actual start date(s)

b) Their project(s) original and/or forecasted finish date(s)

c) % of work completed to date - this can be a subjective estimate accompanied with evidence (NB. The majority of project people do not understand basic Earned value principles so I hold a number of training sessions before I ask them this question)

Why I ask these three questions as a starting point and to exemplify, consider Project X which is a 6 month project that was scheduled to start 1st June 2019 however it actually started 3 weeks late. Forecast finish is now late January 2020 as a consequence although this may change again as the project progresses. At the monthly PCG (Project Control Group to review project performance) held late August 2019 (i.e. half way through the project's timeline), the Project Manager reports that 30% of the work has been completed to date.

There are four scenarios to consider here:

a) The Project is struggling so it must be put on-hold until a proper review is done on causes (e.g. unskilled staff and lack of access to Subject Matter Experts, poor estimating and planning) and options. Options are presented to Sponsor and Steering Committee, let's assume accepted and the project goes on albeit under a different structure and maybe even Project Manager. Current target finish date may still be kept or the finish date may be revised.

b) The project is cancelled as it's not a high priority. Re-direct resources to other projects in the portfolio.

c) The project is put on-hold and possibly resurrected in future. Re-direct resources to other projects in the portfolio.

d) The project will recover ground - however the Project Sponsor and Manager must show how and convince the steering committee that the project can.

In true Earned Value fashion, the earlier you start tracking (i.e. 15% onwards), the quicker you can react and do something about it, or not. Simple, logical and effective. Then add risk and issue reviews and get them to create a schedule in the meantime.