Japan set to choose woman prime minister in landmark first

In the past twenty years, Japan has had more than 10 prime ministers.

Actually, one expert compares assuming the nation's highest office to taking a "poisoned chalice".

However, what is the reason does Japan keep changing leaders? It's due in part of it being a "single-party system", explains Professor James Brown of Temple University in Japan.

The Liberal Democratic Party's control on the political landscape means the primary rivalry comes from inside the party, rather than from external parties.

"So within the LDP there are intense conflicts within different factions - they all want their own faction to get the leadership position."

"Thus although you could be chosen as prime minister, the moment you're in office, you have dozens of people scheming to try to remove you again."

Main Reasons Behind Rapid Turnover

• Single-party rule restricts external competition
• Party infighting drive leadership contests
• The leadership role is frequently called a "cursed position"
• Government continuity stays elusive despite economic strength