We don’t like ROI (return on investment) because solutions the designers and businesses in our community bring to you might not necessarily always have a positive business impact but it can avoid a negative business impact. Its not JUST about whether people love the solution, it's also about considering the damaging effects by asking "what if people hate the solution?".
You give our designers and businesses the symptoms, i.e. you need a new logo because your old logo is ugly. Others will do exactly what you ask them to do. Design advisors don’t. They figure out the cause for the symptom, i.e. diagnose instead of prescribing. Then they provide a solution which surfaces deeper meaning to your business. They will give you a new logo and create NEW business value. The impact is so much more than a linear ROI view.