The part you worked hardest on might not be the selling point.
The part that is most important to you might not be the selling point.
The part you thought would be the selling point might not be the selling point.
The selling point is something that is true about your product that resonates with your market. It’s your job to listen to what they’re telling you and have the guts to refine your marketing even if it’s not one of your favorite aspects.