The effects of reforms are never clear-cut. Many people oppose reform (ex ante) fearing a loss, even if this is not the case (ex post). Conversely, some people may gain a lot (for example those producing exports), but the gains are not immediate. Sometimes, a particular reform will benefit the majority of people, but if each person's gain is small, then they do not have much incentive to mobilize in support of reform, whereas the minority may stand to lose a lot and therefore has a much greater incentive to mobilize against reform. Reform can therefore stall even if, in aggregate, it benefits the majority. This is a good example of what Olson (2001) calls a 'collective action problem', which refers to the difficulties that arise in organizing a group of people to achieve a common objective.