One of the interesting things about lead management software is that although the soft benefits (e.g. running campaigns with less manual effort, more time to focus on the strategic and creative activities that improve marketing ROI) apply to the marketing department, the hard ROI benefits (e.g. more and better quality leads, faster deal cycles, and higher win rates) are primarily seen by the sales department (and of course the company as a whole).
At the same time, companies that can get marketing and sales to stop fighting and instead unite around a single revenue cycle can experience explosive revenue growth, a.k.a. a Revenue Revolution.