Final answer:
Parfaits should be discarded if berries are soft or wilted, the yogurt has separated, or if there is yogurt on the lid rim, which affects presentation and could pose a cross-contamination risk.
Step-by-step explanation:
When serving an assembled Greek Yogurt Parfait, team members should discard the parfait under several conditions to ensure food safety and quality. Firstly, if strawberries or blueberries look soft or wilted, this may indicate spoilage or undesirable quality, prompting the need for discarding the parfait. Secondly, if the yogurt has separated, this is a clear sign of spoilage, as separation often indicates that the product has been stored improperly or for too long. Thirdly, while yogurt present on the rim of the lid may not necessarily indicate spoilage, it does signify poor presentation and potential cross-contamination, which could lead to a decision to discard the parfait based on the establishment's standards.