Projects are typically multi-dimensional. Each alternative can have different benefits, risks and uncertainties.
When preparing an ROI, you owe it to stakeholders to give equal time to citing the upside and the downside of each alternative you present for approval.
Picking the three most promising alternatives out of a set of ten is not easy.
If any of these rely on new technology or rely on a methodology that has not been tested within your organization, chances are you will benefit from a 1-2 day “second opinion” from an outside consultant or domain expert.
Organizations tend to shy away from bringing in outside help.
Some managers feel they should be able to rank projects on their own. The problem with this approach is, unlike a consultant who has seen how other organizations rank and manage different projects across multiple industry areas, the manager will not generally have this experience, making it easy to take a wrong turn.
A second reason is rates. Take the hourly rate of your most senior staff member, multiply that by five and you will be close to the hourly rate charged by the consultant. This sounds expensive until you consider that the overhead for a 1-2 day on site engagement includes two travel days plus some pre/post study time.
If a 1-2 day on-site engagement ends up giving you a good start and saving you 30 days of internal effort, you are getting great value for money.
My area of specialty is facilitating process mapping exercises. I continuously scan the horizon for better, faster ways to help clients become self-sufficient in the area of process mapping, rollout and tracking of run time progress toward Case objectives. When I arrive on site, I have done my homework such that stakeholders can come out of the gate running.
Usually, they never have to look back.