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Why does an aldehyde carbonyl group not need a number in IUPAC names?

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oxidation of alcohols — aldehyde Alcohols may be oxidized to give aldehydes, ketones, and carboxylic acids. The oxidation of organic compounds generally increases the number of bonds from carbon to oxygen, and it may decrease the number of bonds to hydrogen.

In the IUPAC system of nomenclature, the carbonyl group of an aldehyde does not require a number because it must always be located at the end of the parent carbon chain. By definition, the carbonyl carbon is assigned the position of carbon 1, making a numerical locant redundant.1