Gate Review for a Hydration Wearable at DVT Exit
NorthWind, a 14-person startup, is developing a wrist-worn hydration tracker for runners. At the design-validation (DVT) exit gate, 40 units were subjected to a 1.2 m drop test onto concrete. Twelve units cracked at the display flex connector; in four units the display lost function. The connector was selected in EVT to save 0.8 mm thickness. Production tooling worth €180,000 has been committed, launch is 10 weeks away, and 3,000 pre-orders have been taken. Marketing has already announced a “summer launch”. The contract manufacturer can start pilot production in two weeks. A redesign of the connector requires a new flex, a 0.6 mm thicker housing, and an estimated six-week delay. A protective bumper accessory could be shipped with each unit, but it adds €1.10 and changes the industrial design. The quality team proposes a waiver with 100% drop testing. Write a recommendation for the gate review.
1. Identify the stage-gate criteria that are at risk and explain what evidence is missing or weak. Distinguish technical, commercial and regulatory considerations.
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The gate is not a single technical test; it is a risk decision across four criteria. Technically, a 30% drop failure at DVT is a design-mode failure, not a cosmetic issue: the flex connector is the root cause, and 100% drop testing only screens; it does not prevent field failures after repeated drops or at other angles. The evidence is weak because only 40 units were tested, the test does not cover temperature cycling or connector fatigue, and no root-cause analysis (fracture surface, strain gauge) is reported. Commercially, 3,000 pre-orders and an announced launch create schedule pressure, but a field failure rate above the 3% warranty reserve would erase margin and damage the brand. Regulatorily, a wearable is not a safety-critical device, but consumer product safety and EMC obligations still apply; a waiver does not remove them. The weakest evidence is the assumption that a bumper fixes the root cause-it may reduce impact energy but adds cost and changes the ID. A gate decision should therefore be based on root-cause confirmation, a design fix or a validated containment, and a revised risk register, not on the launch date.
2. Recommend one path: proceed with a waiver and bumper, redesign and delay, or another option. Justify with a risk-based argument and specify measurable exit criteria for the next gate.
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Recommendation: redesign the connector and delay launch by six weeks, but run the fix in parallel with a limited, clearly labelled pilot rather than shipping a waiver. The reasoning is that the failure mode is design-related and the cost of a field campaign (3,000 units at €1.10 bumper plus reverse logistics, plus brand damage) exceeds the cost of delay. A waiver with 100% drop testing is not robust: it cannot test every drop orientation, and it transfers risk to users. The bumper is a temporary mitigation, not a corrective action. Exit criteria for the next gate should be measurable: zero failures in 40 drop tests at 1.2 m onto concrete, including 10 units conditioned at −10 °C and 40 °C; no loss of display function after 500 connector mating cycles; a root-cause report signed by design and quality; and a process FMEA updated with the new flex. Commercially, offer pre-order customers a choice of a delayed shipment with a small credit or a cancellation, and do not claim the original date. The pilot batch of 100 units should be built with production tooling and tested before full ramp.
3. Outline how you would communicate the decision to pre-order customers and the sales team, including what you would not say.
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Communicate in three layers. To pre-order customers: a short, factual email stating that the drop test found a connector issue, that shipments will move by up to six weeks, and that they may cancel for a full refund or keep the order with a €15 credit. Do not say the product is 'unsafe' unless the risk assessment supports that; do say what was found and what is being changed. To the sales team: a briefing pack with the revised date, the reason, the customer script, and an FAQ covering refunds, the bumper decision, and warranty. To the contract manufacturer: a written change notice and a revised pilot build plan. Avoid blaming the supplier or promising a date that has not been validated by the new drop test. Keep a decision log and a risk register so the gate review is auditable. The goal is to preserve trust by being specific about the defect and the fix, not by minimizing it.