The basic aim of this paper is an attempt to examine the phenomenon of qualitative differentiation, including the answer whether the improvement of product quality through an increase in its durability, is an appropriate, at the present times, way how to build a market advantage by the manufacturer of agricultural machinery, including manure spreaders. As part of the study, attempts to answer the question of whether, and if so, the differentiation of a complex product by increasing durability (quality) of its components, is the right strategy, taking into account the higher cost of production, have been made. For this purpose, a comparison of the cost of manufacturing the product comprised of higher quality components with the cost of the effects caused by a defect resulting in a product of lower quality. Taking up the discussion on the specific issues, the conceptual model of the thesis, corresponding to the listed paper's objectives, has been adopted, namely: the cost of the effects caused by a defect in a complex product is growing very rapidly with the distance between the moment of occurrence of defect and the time it was discovered, which confirms the expediency of manufacturing higher quality products, even at the expense of the originally assumed profit.