Tessa in your comments you use a couple of examples that I think destroy your original argument. You're hired to paint a wall - what if more than one person occupies the space the wall surrounds? How do they come to an agreement about the colour? Same with your transport example - who decides that the rail track is the best method or that it is even necessary or what is the most appropriate route using what criteria. All these aspects of the decision require debate and compromises. That is politics, whether you like it or not.