Why do the Prime Ministers of Japan change so quickly ?
Many foreigners often ask me this question. It is true that during the last 20 years, there has been fourteen different people to take office as the Prime Minister of Japan, and the average term has only been 18 months.
This is a problem that we have to think about seriously.

Superficially there are a few reasons, for example, scandals, health problems, election defeats, gafts and so forth. But essentially this issue can be analyzed from both poor personnel choices and changes in the political environment.

The most important factor being unsuitable candidates leading to a lower quality of Prime Minster in Japan. Recently it seems that public opinion polls are strongly dictating Japanese politics. Therefore the person who gains popularity through public opinion polls tends to be elected as the Prime Minister of Japan. Modern politics depend too greatly on the public opinion polls, which unfortunately does not necessarily correspond to ability or quality.

This change in the political landscape has brought forward the era of two big parties. With masses now beginning to require dramatic results in politics. However, these people calling for change don't belong to a specific party.
They are called "Mutouha-sou" in Japanese and they change the parties every election according to the political circumstance.

Mutouha-sou affects public opinion polls and are influenced greatly by political TV shows. I think a few of these TV stations have unclear agendas concerning politics and are sometimes doubted of their fairness. Surprisingly, a lot of statesmen in the Diet tend to be unnerved by public opinion polls.
When an approval rating for a cabinet is below 30%, voices to change the Prime Minister usually start boiling over from members of the ruling party. This fact applies to both the LDP and DPJ.

Thus the Prime Minister of Japan has changed so freaquently.