One of the most common mistakes in business cases and proposals is the failure to consider and present all benefits.
Here is what you need to look for:
1. Quantitative (“hard”) benefits. These are benefits that can be translated into cash value. These usually arise as 
  • cost savings
  • new revenue
  • expenditure avoidance, and so on.  
2. Capacity benefits. Some benefits result in freeing up of a resource, such as people or people’s time or office space. These benefits are often erroneously counted as “hard”.
In one instance, we once audited a business case where the authors (a well known consulting company) stated that the proposal will free up two hours a day for each of 80 employees making $25/hour. And so they stated that the case would deliver close to a million dollars a year in savings. On the same breath, they stated that there would be no reduction in workforce.
Well, this is just plain wrong.
3.Qualitative (“soft”) benefits. This is a diverse group that includes such considerations as
  • strategic value
  • adoption of best practices
  • morale improvement
  • rationalization of business processes
  • image enhancements, and so on.
Are hard benefits more important than the soft ones ? Not at all! Although it is impossible to tell upfront, each organization will have its own set of prioroties at any given time, and these priorities, strategic and tactical, will define the weighting scheme (spoken or unspoken) which decision makers will utilize while making the decision.