Even with large majorities of their own party in Congress, presidents experience difficulty in exercising legislative leadership because the president must compete against state governors for influence
A the weak nature of political parties hampers the president’s ability to control Congress
B the president’s use of the veto is ineffective with Congress
C individual members of Congress attract greater publicity when challenging the president
D the president seldom addresses the same issues as members of Congress

In the political literature it has been argued that a president is strong when defining policies, and therefore has the capacity to carry out his agenda; on the contrary, weak presidents are when their assemblies are what define the agenda, they have no independent constitutional authority over the legislation; and they are very weak if they lack control of a majority party.

Congress must, by definition, control the government in a representative democracy, also in modern presidentialism.

When legislators who are members of a party recognize that these institutes have a weak institutionalization and volatility that leads to a crisis of party systems.