It’s difficult to predict the Return On Investment (ROI) for Graphic design.
Graphic Design is often an afterthought or an obligatory step in the business process.
Update: April 21, 2015 — Google will now demote websites in search results that are not mobile friendly. Therefore it is crucial to implement responsive web design if you don’t want to lose visitors.
The proliferation of smartphones and tablets means that Mobile and the Web are increasingly consolidating, hence Responsive Web Design is now the benchmark.