The lifecycle of a customer is guided by a marketing process that nurtures them through various stages, from initial awareness to becoming a brand advocate. The length and complexity of the lifecycle vary depending on the product or service being sold, with some requiring continuous nurturing to ensure repeat business, while others have shorter lifecycles where immediate re-engagement is necessary. The stages include awareness, engagement, evaluation, purchase, loyalty, and upselling, each requiring different strategies to build trust, educate customers, and foster long-term relationships. Implementing a solid customer onboarding process is crucial throughout the lifecycle to ensure customers start off on the right foot and stay engaged with the brand over time.