Ecotech Services sells a range of second hand equipment that has been repaired or refurbished. We can offer a warranty on the equipment without fear of incurring high costs (resulting from warranty repair or for refunds) to us for a number of reasons, including our experience on failure modes and the typical faults that are expected, and because of our judgement on where it lies on the bathtub curve.
The bathtub curve is a concept in engineering that describes the reliability of a product during its lifetime. It shows that a product is more likely to fail when it is very new or very old.
In our experience the bathtub curve does appear to be applicable for a wide range of commercial, industrial, and consumer products. However, since we don’t often have reliable data on total product sales versus number of product failures our evidence on the veracity of the bathtub curve is merely anecdotal.
If the bathtub curve is valid for a particular product and we sell it during the constant failure rate section of the curve, then we can quite rightly make the claim that they are statistically more reliable than new ones. This is assuming that we correctly assess that the product is not in the increasing failure rate of the curve, and that the manufacturer has sold the product with a minimal burn in. These are both reasonable assumptions.