The best upsell conversations start with the customer's success: "You have achieved X with our product. Based on your goals, feature Y could help you achieve Z." Value first, always.
Strong answers show: deep understanding of the customer's business and goals, identifying genuine needs that additional products address, timing expansion conversations around value realisation, using usage data and success metrics to support the case, and maintaining the trusted adviser relationship throughout.
Tests account management and relationship skills. Candidates who push products without understanding customer needs damage relationships. Those who expand accounts based on genuine value creation are far more sustainable.