Provenance
Where it comes from.
'Fan,' in the enthusiast sense, is American English from 1889, first among baseball crowds, as a clipped form of 'fanatic,' from Latin fanaticus, 'inspired by a god,' from fanum, 'temple.' The devotion in the word is old; the shortening is modern.
The ending '-ify' is the familiar English verb-maker, from Latin -ficare (a form of facere, 'to make'), the same piece that gives us clarify, amplify, and simplify. Joined to 'fan,' it turns a feeling of devotion into something a brand can actively do.