Cast your mind back to the session we had with Ian Tapster about the global financial crisis of 2008 in which the banks indulged in reckless, and in some cases criminal, lending practices. Their subsequent collapse precipitated a global recession.
This hit the UK when the Labour Party was in power, and was compounded by a widespread spending programme here in the UK on public services, which is part of Labour ideology. Of course, when the crisis hit, and it became clear that the UK could not sustain it's national debt, with an overall deficit of many billions of pounds, the Labour party began to lose credibility in its handling of the economy. When the Conservative/Liberal coalition government took over in 2010, the Tory administration began to lay the blame for the national deficit at Labour's door, although it was an international crisis. Their successful blackening of the Labour party resulted in the Conservative victory in 2015, giving us a Conservative government in the UK.
Since 2010, the government policy has been to reduce the national deficit. Because we are a Tory-led country, the subsequent austerity programme, which was brought in to reduce the deficit, is also an ideological approach because the Conservative party believes in a market economy, not a welfare state. Therefore, the position is that the global financial crisis highlighted countries' dependence on credit and the every increasing level of debt, but in Britain, the need for austerity was exacerbated by a Conservative government who believe in cutting the public sector as an ideological imperative. So you have two major influences on a programme of public sector cuts
1. The fallout from the global financial crisis of 2008 and the subsequent global recession
2. A Conservative government who wish to remove the welfare state and cut the public sector, presented under the guise of reducing the deficit and paying off our national debt.
In fact, it is widely documented that our national debt, and the deficit have both increased massively under the Tory party government.