3.1.3 MTBF Score
Each segment sets a 5,000 hour range for MTBF (Mean Time Before Failure), the number of hours a product is expected to operate before it malfunctions. Customers prefer products towards the top of the range.
MTBF Rough Cut
Demand scores fall rapidly for products with MTBFs beneath the segment’s guidelines. Products with an MTBF 1,000 hours below the segment guideline lose 20% of their customer survey score. Products continue to lose approximately 20% of their customer survey score for every 1,000 hours below the guideline, on down to 4,999 hours, where the customer survey score is reduced by approximately 99%. At 5,000 hours below the range, demand for the product falls to zero.
MTBF Fine Cut
Within the segment’s MTBF range, the customer survey score improves as MTBF increases (Figure 3.3). However, material costs increase $0.30 for every additional 1,000 hours of reliability. Customers ignore reliability above the expected range– demand plateaus at the top of the range.