For foreign business people, Japanese contracts are too abstract or vague in many cases.
Because of relationship oriented culture, the Japanese contract is to summarize the agreement and the willingness to start the business together rather than clarifying clear responsibilities as the promises, the limitations, and the exact period. So Japanese contract is prepared being flexible based on mutual trust to be able to renegotiate when something happened. Going to court means the end of a relationship. So sometime, to request detailed stipulations would create a lack of trust.
Large Japanese companies have been changing, but there are still many Japanese companies are not so comfortable with a contract focusing on legal.