Everything is stable, the policy image, the policy monopoly and then BAM, a major shift occurs. “What just happened?” says everyone, in shock. That’s the job of theory, to explain (if not predict).
See also Punctuated Equilibrium
“Dramatic changes—Baumgartner and Jones call these policy punctuations—alternate with long periods of stability. Thus, sometimes, sudden sweeping movements challenge closed subsystemic politics: policy monopolies collapse, high politics gets temporarily heavily involved until the policy domain at stake is contracted out again to a small group of experts and stakeholders; a new policy monopoly gets established.”
(Walgrave and Varone, 2008:367)
“John and Bevan (2012) create a three-point typology of punctuation comprising procedural changes, high and low salience punctuations using the case of the UK from 1911 to 2008,” (Petridou, 2014: 219)
John, Peter, and Shaun Bevan. 2012. “What Are Policy Punctuations? Large Changes in the Legislative Agenda of the UK Government, 1911–2008.” Policy Studies Journal 40 (1): 89 107.