My stepdad manages a team in IT for a very large, very slow company in the banking/financial sector. The decisions about what software and hosting solutions they'll use are made by execs at the upper echelons, probably over games of golf by people who don't know that much. They just know, "I really like Jim over at IBM, he's got a real swagger to his step" and "other big companies are using them" and "hell they just bought a Super Bowl commercial." So a $2M deal gets done, and IBM stays in business.