It goes back to the beginnings of the company. It was run by bowlers, and they put a lot of guys on staff over the years to both get the message out, and get feedback on equipment. They grew up in the resin era, and although Columbia and Track originally had better resin balls in the early mid 90s, Storm had some great break throughs with the Bolt, and El Nino that caught them a lot of the market by 2000. Storm was further helped by Columbia and Brunswick business decisions. Columbia basically bet the company on the epoxy ball which was a failure, and probably ultimately lead to their demise.
Brunswick went another direction with technology at the same time they opted to move to Mexico. The Furys Wilds, and C System balls were not as good as the infernos and Zones they replaced. Whether it was design, or quality control, who knows, but it made the decision for a lot of people to go another direction easy at the time.
Ebonite has always suffered from the perception that their shells don't hold up without meticulous maintenance beyond what a lot of bowlers are willing to invest.
At the end of the day, Storm makes very good equipment, and nobody is better to their bowlers than Storm.