Introduction

Social movements are goal-oriented actions undertaken by people aiming to achieve personal benefits, group advantages, public goods, and/or social justice. The likelihood of achieving the desired goals thus constitutes a major factor influencing the emergence of specific movements (McAdam, 1982) and individuals’ willingness to participate in collective action (Klandermans, 1997). After a collective action campaign begins, participants and activists are likely to continually re-evaluate the probabilities of various outcomes (Einwohner, 2002). Such evaluations may then shape people's willingness to persist and their judgments of what strategies the movement should adopt (Corrigall-Brown, 2012).

The conventional arguments listed above highlight the role of instrumental rationality in protests. This emphasis on instrumental rationality has been a staple in social movement studies since at least the 1970s (McCarthy and Zald, 1977). However, there are also times when people protest even though the possibility of success is slim, and there are protests and movements that are seemingly not driven by cost-benefit calculations. Specifically, the wave of large-scale occupation protests around the world since 2011, such as the Arab Spring and Occupy Wall Street, has taken on new characteristics (Castells, 2012) and arisen based on a different “action logic” (Bennett and Segerberg, 2013). In this wave of protests, perceived chances of success and cost-benefit calculations were seemingly replaced by spontaneous actions based on shared outrage and an urge to express it.