The political scene in most countries is basically dominated by an explicit or implicit two-party system, most commonly described as 'left' and 'right'.
Even countries with a multitude of political parties represented in the legislative body ultimately are governed by either a coalition of left-or rightwing parties. The exact composition of the coalitions may change from time to time but the general drift of the political intent of its components does not alter much over time.
So it is no wonder that from time to time there are calls for a 'third party' to give voters a real alternative to the policies supported by the dominant parties. In their fight to grab tiny percentages from the other side the party strategists tend to hug a 'middle-of-the-road' ideology which makes the policies virtually indistinguishable for the citizen. As the two political side from time form 'grand coalitions' voters in these periods are left with no political alternative at all and have to submit to a quasi-dictatorial regime.
A constitutional system of direct democracy offers a viable solution to this problem as voters would be able to exert direct influence on all legislation thus circumventing the oligopoly power of the existing party system.