Is there something missing from this list that also influences Market Share

This is a discussion board about BUSINESS STRATEGY GAME. Please answer this question only if you know BSG before.

Question is:

Marketing, Celebrity Endorsement, and Market Share – are there relationships in the BSG among these three factors? If so, what are they? Is there something missing from this list that also influences Market Share? Describe what that could be.

One page. You can find the answer to the question from the resource below (players quide).

players_guide