There is increasing concern about high rates of dropout from universities, especially among students from disadvantaged backgrounds. In the UK this is related to recent changes in higher education policy, especially the imposition of a higher fees regime and the uncapping of student numbers. While recent research has explored the demography of students who drop out, less is known about the reasons for dropping out, or indeed the reasons why some students who are unhappy with their student experience nonetheless stay on. This article uses data from a longitudinal qualitative study, the "Paired Peers" project funded by the Leverhulme Trust, to explore this issue in detail. A typology of reasons for dropping out is offered: homesickness; loneliness and a sense of not fitting in; problems with academic study, including having chosen the wrong course; and money issues. The first two appear the most powerful; the notion of "fish out of water" derived from the work of Bourdieu and Wacquant (1992) is used to explain it. The article also explores the motivation of those who experience these problems and report high levels of stress, but nevertheless decide to stay on.