Choice is all about gratification. A preference for one thing is paid for by the sacrifice of other things. This means that there are different kinds of choices.
The vertical axis captures the environment of choice, including the constraints on competition among the myriad claims of recognition or satisfaction by one or more sets of interests whose private preferences are being imposed on public objects. The horizontal axis is concerned with the scale of participation in the choice to be made. As Kenneth Arrow (1951) and Mancur Olson (1965) have demonstrated, the number of participants is a major if not the major determinant in the process of choice and the prospect of choices that are satisfactory to all concerned. This is the origin of the quest for 'rational choice.'