What should athletes understand about the sponsorship relationship from the very beginning?

Sponsorship is a two-way street where you must add value to your partner. Don't go after sponsors just for the sake of getting a sponsorship, and don't have unrealistic expectations. Until you're winning championships, you're earning your keep and must prove yourself every year. Even at the amateur level getting pro-form deals or discounts, treat it as a business relationship - bring value through things like getting friends and family to shop at sponsor locations, promoting them authentically, and understanding that whatever you receive must be matched with value in return.