A social media platform designed to reward fans for loving artists is gaining traction with some of music’s most passionate fandoms, including Taylor Swift’s “Swifties” and Harry Styles’s “Harries.” Fave founder Jacquelle Amankonah Horton attributes some of her company’s success to her 40-year music-technology veteran advisor, Kelli Richards. WSJ’s ‘Making the Founder’ takes a candid look back on Jacquelle and Kelli’s relationship. Illustration: Preston Jessee for the Wall Street Journal