Parkinson's law is the adage first articulated by Cyril Northcote Parkinson as part of the first sentence of a humorous essay published in The Economist in 1955:
Work expands so as to fill the time available for its completion.
Rather, he assigns to the term the rate at which bureaucracies expand over time. Much of the essay is dedicated to a summary of purportedly scientific observations supporting his law, such as the increase in the number of employees at the Colonial Office while Great Britain's overseas empire declined (indeed, he shows that the Colonial Office had its greatest number of staff at the point when it was folded into the Foreign Office because of a lack of colonies to administer). He explains this growth by two forces: (1) "An official wants to multiply subordinates, not rivals" and (2) "Officials make work for each other." He notes in particular that the total of those employed inside a bureaucracy rose by 5-7% per year "irrespective of any variation in the amount of work (if any) to be done".
In 1986, Alessandro Natta complained about the swelling bureaucracy in Italy. Mikhail Gorbachev responded that "Parkinson's Law works everywhere". Contents
In time, however, the first-referenced meaning of the phrase has dominated, and sprouted several corollaries: for example, the derivative relating to computers:
Data expands to fill the space available for storage.
Storage requirements will increase to meet storage capacity.
"Parkinson's Law" could be generalized further still as:
The demand upon a resource tends to expand to match the supply of the resource.
An extension is often added to this, stating that:
The reverse is not true.
This generalization has become very similar to the economic law of demand; that the lower the price of a service or commodity, the greater the quantity demanded.
Some define Parkinson's Law in regard to time as:
The amount of time which one has to perform a task is the amount of time it will take to complete the task. Source: Wikipedia