In recent years, the United Kingdom (UK) has shown itself to be more likely than many of its European neighbours to arrive at unexpected economic – and especially political decisions. A number of factors underpinning the structure and evolution of the British state, along with its legal and institutional system, help to explain the tensions at the heart of the "insecurity cycle" as well as the mechanisms that contribute to its dynamism. The nature of the constitution is not the only influence that contributes to the adversarial nature of the British institutional structure; the separate evolution of corporate and financial law. The British poor law was a remarkably enduring institution which had its origins in the post-feudal economy of the late middle ages and persisted up to foundation of the modern welfare state during the middle decades of the twentieth century. The evolution of Britain's electoral and political system has also played a role in the cyclical nature of policy.