There are many instances where machines are inoperable, sometimes at critical periods in the production of a crop, because either a replacement part or the skill to fit it is unavailable. Other instances of less immediate consequence but nonetheless unsatisfactory, are where parts are prohibitively expensive, where the level of operator or service/repair skill is too low, where machinery is incorrectly used or mismatched or where soil and climatic conditions cause greater than anticipated replacement and repair problems. In addition, despite general acceptance that all machinery needs regular maintenance and a varying amount of repair during its working life, the full cost of that repair and maintenance is less widely accepted and is sometimes overlooked or ignored.
A recent study shows that with the exception of machinery with few or no moving parts, the cost of repairs and parts for agricultural machinery in developing countries may range from 130 to 400% of the initial cost of the machinery; these figures are substantially higher than those experienced in developed countries.