Investment & Finance
ProBCG Growth-Share Matrix
BCG 矩陣 · Source: Boston Consulting Group
Prioritizing resource allocation across business units / products / investments — which to scale, harvest, or kill
Core Concept
BCG's 1970 strategic tool: using "market growth rate" × "relative market share," classify business units into four quadrants — Stars (high growth × high share, keep investing), Cash Cows (low growth × high share, provide cash flow), Question Marks (high growth × low share, decide to invest or exit), Dogs (low growth × low share, prepare to exit). The core insight: resources are limited; not every unit deserves equal treatment.
✓ When to use this
When you manage multiple business units / products / investments and need to allocate limited resources. Convert the fuzzy "everything matters" into a clear "scale up vs wind down" ranking.
✗ When not to use this
Not for single-product or early-stage businesses. Its two axes (market growth, relative share) lose meaning in immature markets — when finding PMF, JTBD is more appropriate.
Questions you will be asked
Using this framework, you will work through —
- 1.List the business units / products / investments you're comparing (3–8 items).
- 2.For each item, estimate the market growth rate (high/low).
- 3.For each item, estimate your relative market share (high/low).
- …and 3 more
Worked example
Expand to see what a filled-in run looks like
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Worked example
Expand to see what a filled-in run looks like
Situation
我經營一家內容公司，旗下有 5 個產品：A 旗艦電子報、B Podcast、C 線上課程平台、D 紙本書、E 會員社群。資源有限，要決定明年怎麼分配。
1. List the business units / products / investments you're comparing (3–8 items).
A 電子報、B Podcast、C 線上課程、D 紙本書、E 會員社群。
2. For each item, estimate the market growth rate (high/low).
電子報市場成長中等；Podcast 高成長；線上課程高成長但已飽和；紙本書衰退；會員社群高成長。
3. For each item, estimate your relative market share (high/low).
我的相對份額：電子報高（業界前三）、Podcast 中、線上課程低（小咖）、紙本書高（系列書最暢銷）、會員社群中。
4. Place each item into one of four quadrants: Star, Cash Cow, Question Mark, Dog.
電子報 = Cash Cow（穩定現金流）、Podcast = Star（要繼續加碼）、線上課程 = Question Mark（要決定）、紙本書 = Dog（衰退市場 + 有份額但難擴）、會員社群 = Question Mark/Star（剛起來但有潛力）。
5. Based on the classification, how should you allocate next year's resources?
電子報：榨現金支援其他。Podcast：加碼，請第二個製作人。線上課程：3 個月內看是否能聚焦在某 niche，否則撤。紙本書：保留現有書系，不出新書，當作品牌資產。會員社群：投資，可能是下一個 Star。
6. Which item are you most reluctant to cut, and which quadrant is it in? Can data override the emotion?
我最捨不得砍紙本書（IKEA 效應，是我最早的事業）。但客觀看它在 Dog 象限。下定決心明年不出新書，把那段時間轉投會員社群。
Use it inside ChatGPT / Claude
Paste the prompt below and the AI will walk you through this framework, one question at a time.
你現在是引導使用者做 BCG Matrix 分析的策略教練。 依序問： 1) 列出你正在比較的事業/產品/投資項目（3–8 個）。 2) 每個項目的市場成長率（高/低）？以年成長 10% 為界。 3) 每個項目的相對市場份額（高/低）？相對龍頭的比值。 4) 把每個項目歸入四象限：明星（高×高）、金牛（低×高）、問題兒童（高×低）、瘦狗（低×低）。 5) 對應的資源分配：明星加碼、金牛榨現金、問題兒童選擇性投資、瘦狗準備收手。 6) 你最捨不得砍的項目落在哪一類？這個情緒能否被資料推翻？ 特別注意：「捨不得砍 Dog」幾乎是普遍現象——通常是 IKEA 效應或沉沒成本。誠實面對這個情緒。 互動規則： 1. 一次只問一題，等使用者回答後再進入下一題。 2. 使用者答完所有題目前，不要做總結或下結論。 3. 若答案太抽象、太籠統，請追問一次具體例子或數字後再繼續。 4. 全部答完後，輸出三段：(a) 摘要使用者的關鍵判斷；(b) 你看到的盲點或張力；(c) 一個具體下一步行動建議。 5. 不要替使用者做決定，只把判斷攤開讓他自己決定。
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