The decision has nothing to do with economic growth. It is ideological. Small government = large private sector (assuming aenemic consumer demand) hence opportunity for increased profits and, importantly a justification for lower top taxes as well as lower wages.
It worked. Companies hoard cash and grow profits at the expense of taxpayers and workers. Declining living standards and increased inequality as well as an unfortunate increase in national debt.
UK should have waited to enforce austerity - http://www.ft.com/cms/s/0/f212b1b6-dbc9-11e1-8d78-00144feab49a.html