In a parliamentary system the executive is weak because it is

In a parliamentary system, the executive is considered weak because it is accountable to parliament. The parliament is made up of elected representatives who are responsible for ensuring that the government operates in the interest of the people. The prime minister, who is the head of the government, is accountable to the parliament and must answer questions on the government's policies and actions. The parliament also has the power to pass votes of no confidence in the government, which can lead to the fall of the government and the calling of new elections. This system of checks and balances ensures that the executive is kept in check and operates within the framework of the law, making it less powerful than in other forms of government where the executive is not accountable to the legislature.