The high volume market puts pressure on manufacturers for two main reasons: (1) high volume implies low prices and significant market elasticity, and (2) these markets are always characterised in a free market economy by tough competition. The need to remain ahead of the competition means that new, improved and more reliable products are a continuous necessity and the development-to-shipment time is progressively being shortened. This tendency has developed over many years and covers all consumer durables. The major factor which has an influence on the price, is the manufacturers' ability to delivery long term reliability without having to meet the cost of large numbers of warranty claims. Only a small over-estimation of the product's reliability can lead to warranty claims seriously eroding the profit on the product. This article discusses, in general terms, the techniques which can be applied to give the manufacturer confidence that the warranty periods being offered are realistic.