I found this story about The Evolution of Sharpie very instructive please note particularly:
“Customers have also driven Sharpie’s latest shift — into the realm of self-expression. “We [asked customers] to ‘show us what you started with Sharpie’” via social media channels, Gambhir said. “We waited to see if it would work — and it did…. People were using Sharpies in more ways than we could possibly imagine.