What is the theoretical impact of the erosion of partisan ties on electoral abstention? This question comes from Downs-North's theory of political ideology, which is a tool to reduce the cost of understanding the political debates. Then, when the left-right political divide becomes less visible, the costs of understanding political debates rise and electoral abstention occurs. This interpretation of abstention has three implications: first, it shows that among the multiple reasons responsible for the 'democratic crisis' in France, the weakening of the traditional notion of the left and the right is significant. Second, it highlights that voters' level of education and the Downsian theory of programme convergence affect electoral behaviours and political entrepreneurship. Third, it explains why the relationship between abstention and economic crisis is nonlinear.