Here are a few options for the description, considering different nuances and purposes:

**Option 1: Concise and Descriptive**

* **Description:** 調解程序未能達成協議。
* **Translation:** Negotiation process failed to reach an agreement.
* **Use Case:** Simple, direct, and suitable for general use.

**Option 2: Focusing on the Consequence**

* **Description:** 協商破裂，案件可能進入訴訟或其他法律途徑。
* **Translation:** Negotiations broke down, and the case may proceed to litigation or other legal channels.
* **Use Case:** If the post discusses the next steps after failed mediation.

**Option 3: Highlighting the Effort**

* **Description:** 努力進行調解，但最終未能解決爭端。
* **Translation:** Efforts were made to mediate, but the dispute ultimately could not be resolved.
* **Use Case:** If the post emphasizes the effort involved in the mediation process.

**Option 4: Emphasizing the Outcome**

* **Description:** 調解未果，結果未能達成和解。
* **Translation:** Mediation failed, and a settlement could not be reached.
* **Use Case:** When the post focuses on the lack of settlement.

**How to choose the best option:**

* **Consider the context of your post:** What is the main focus of your article?
* **Think about your target audience:** What level of detail do they need?
* **Be consistent:** Use a description that aligns with the overall tone and content of your website.

For most general uses, **Option 1: Concise and Descriptive** is a good starting point. Remember to add this description when creating or editing the post tag on WordPress.