biz-bcg-matrix

asgard-ai-platform ｜ 商業與營運 ｜ 原文 ｜ MIT

用 BCG 矩陣分析產品組合，決定投資、收割或撤出

---
name: "biz-bcg-matrix"
description: "套用 BCG 成長-占有率矩陣，分析產品或事業單位的投資組合，用於資源配置決策。當使用者需要在多個產品之間排定投資優先順序、決定哪些產品要加碼、收割還是撤出、或評估投資組合是否平衡時使用，即使他們說的是「我們該投資哪些產品」或「投資組合策略」，沒提到 BCG 也一樣。"
metadata:
  category: "WP-13 商學院—策略"
  tags: ["business-strategy", "bcg-matrix", "portfolio-management"]
---

# BCG 成長-占有率矩陣

## 概述

BCG 矩陣依市場成長率（Y 軸）和相對市場占有率（X 軸），把產品或事業單位分成四個象限。它引導資源配置：該在哪裡投資、哪裡收割現金、什麼該撤出。

## 何時使用

**觸發條件：**
- 使用者管理多個產品或事業單位，需要排定優先順序
- 使用者問「哪些產品該投資、哪些該砍？」
- 使用者需要事業的投資組合層級視角
- 使用者提到「cash cow」、「明星產品」或「投資組合策略」

**何時不要用：**
- 單一產品的策略 → 用 SWOT 或藍海策略
- 產業層級的分析 → 用 Porter 五力
- 需要詳細的財務模型時 → 用 DCF 或財務比率

## 框架

```
鐵律：用相對市占，不是絕對市占

X 軸是「相對」市場占有率 = 你的市占 / 最大競爭對手的市占。
在領導者占 40% 的市場裡，你占 20% = 0.5x（低）。
在第二大對手只占 10% 的市場裡，你占 20% = 2.0x（高）。

絕對不要用絕對市占。沒有看到領導者的市占，
30% 的市占什麼都說明不了。
```

```
鐵律：先畫圖，再談策略

在決定策略「之前」，先把「所有」產品／單位放到矩陣上。
投資組合的平衡很重要：只有明星產品的公司會有現金危機
（明星產品會耗現金）。只有金牛產品的公司，沒有成長的管線。
```

### 步驟 1：定義投資組合的單位

列出所有要分析的產品、產品線或事業單位。每一個都必須：
- 是有自己市場和競爭對手的獨立單位
- 在營收、市占和市場成長方面是可衡量的

### 步驟 2：蒐集每個單位的資料

對每個單位，確定：
- **市場成長率**：整個市場的年成長率（不是你自己的營收成長）。通常 >10% = 高成長。
- **相對市場占有率**：你的市占 ÷ 最大競爭對手的市占。>1.0x = 高。

### 步驟 3：畫到矩陣上

| | 高相對市占 | 低相對市占 |
|---|---|---|
| **高市場成長** | ⭐ **明星（Stars）**：在成長市場中占有率高。能創造營收，但為了維持地位會消耗現金。 | ❓ **問號（Question Marks）**：在成長市場中占有率低。需要大量投資來搶占有率，否則就撤出。 |
| **低市場成長** | 🐄 **金牛（Cash Cows）**：在成熟市場中占有率高。只需少量投資，就能產生剩餘現金。 | 🐕 **瘦狗（Dogs）**：在緩慢的市場中占有率低。產生的現金極少，潛力有限。 |

### 步驟 4：決定每個象限的策略

| 象限 | 預設策略 | 細微之處 |
|----------|-----------------|--------|
| 明星 | **投資**，維持／擴大占有率 | 市場成熟後會變成金牛 |
| 金牛 | **收割**：以最少的投資，把現金榨取到最大 | 為明星和部分問號提供資金 |
| 問號 | **選擇性投資或撤出**：挑出贏家、砍掉輸家 | 最關鍵的決策，不是每個都能變成明星 |
| 瘦狗 | **撤出或重新定位** | 如果和其他單位有綜效，可以保留 |

### 步驟 5：評估投資組合的平衡

檢查整體投資組合的健康度：
- **健康**：金牛（提供資金）+ 明星（成長）+ 1-2 個問號（管線）的組合
- **不健康**：全是金牛（沒有成長）、全是明星（現金流失）、全是瘦狗（衰退）

## 輸出格式

```markdown
# BCG 矩陣分析：{公司/投資組合}

## 投資組合單位

| 單位 | 營收 | 市場成長 | 相對市占 | 象限 |
|------|---------|--------------|-------------------|----------|
| {產品 A} | {$X} | {X%} | {X.Xx} | 明星/金牛/問號/瘦狗 |

## BCG 矩陣配置

| | 高占有率（>1.0x） | 低占有率（<1.0x） |
|---|---|---|
| **高成長（>10%）** | ⭐ {列出明星} | ❓ {列出問號} |
| **低成長（<10%）** | 🐄 {列出金牛} | 🐕 {列出瘦狗} |

## 策略建議

### 明星：投資
- {產品}：{具體的投資建議}

### 金牛：收割
- {產品}：{如何把現金榨取到最大}

### 問號：決定
- {產品}：投資 / 撤出，{理由}

### 瘦狗：撤出／重新定位
- {產品}：{建議}

## 投資組合健康度評估
{整體平衡的評估和再平衡的建議}
```

## 範例

### 正確的應用

**情境：** 一家有 4 條產品線的台灣電子公司的 BCG 分析

| 單位 | 市場成長 | 相對市占 | 象限 | 推理 |
|------|-------------|-----------|----------|-----------|
| 筆電產品線 | 3% | 1.8x（領導者） | 金牛 ✓ | 成熟市場，地位主導 |
| 電競周邊 | 18% | 0.4x | 問號 ✓ | 快速成長，但是小型業者 |
| 伺服器零組件 | 12% | 1.2x | 明星 ✓ | 成長市場，領先地位 |
| 傳統手機 | -2% | 0.3x | 瘦狗 ✓ | 衰退的市場，占有率極低 |

**策略**：收割筆電的現金 → 供給伺服器（維持明星）+ 選擇性投資電競（有潛力的問號）。撤出傳統手機。

### 錯誤的應用

**情境：** 同一家公司

**哪裡出錯：**
- 用絕對市占（25%），而不是相對市占（25% / 領導者的 30% = 0.83x）→ 會把實際上屬於低占有率的單位，誤分類為高占有率。違反鐵律。
- 沒先畫圖就決定「每個都投資」→ 沒有投資組合的取捨分析。違反鐵律：先畫圖，再談策略。

## 常見陷阱

- **市場成長 ≠ 你的營收成長**：一個產品成長 20%，但市場成長 25%，代表它在流失占有率。要用市場成長率，不是公司的營收成長。
- **相對占有率的門檻**：1.0x 的分界只是參考準則。在沒有明確領導者的分散市場，要調整門檻，並記錄你的理由。
- **BCG 是快照**：市場會演變。明星會變成金牛，問號會變成瘦狗。要每年重新評估。
- **BCG 忽略綜效**：一個替「明星」提供關鍵零組件的「瘦狗」，可能值得保留。要把跨單位的相依性納入考量。
- **不是所有問號都有資金可投**：這是最難的決定。要用額外的標準（市場適配度、團隊能力、策略重要性）來選出該投資哪些。

## 參考資料

- GE-McKinsey 矩陣這個替代方案（多因素版本），見 `references/ge-mckinsey.md`
- 與其他策略框架的比較，見 `references/framework-comparison.md`

---
name: "biz-bcg-matrix"
description: "Apply BCG Growth-Share Matrix to analyze a product or business unit portfolio for resource allocation decisions. Use this skill when the user needs to prioritize investments across multiple products, decide which products to grow vs harvest vs divest, or evaluate a portfolio's balance — even if they say 'which products should we invest in' or 'portfolio strategy' without naming BCG."
metadata:
  category: "WP-13 商學院—策略"
  tags: ["business-strategy", "bcg-matrix", "portfolio-management"]
---

# BCG Growth-Share Matrix

## Overview

The BCG Matrix classifies products or business units into four quadrants based on market growth rate (Y-axis) and relative market share (X-axis). It guides resource allocation: where to invest, where to harvest cash, and what to divest.

## When to Use

**Trigger conditions:**
- User managing multiple products or business units and needs to prioritize
- User asks "which products should we invest in vs cut?"
- User needs a portfolio-level view of their business
- User mentions "cash cow", "star product", or "portfolio strategy"

**When NOT to use:**
- For single-product strategy → use SWOT or Blue Ocean
- For industry-level analysis → use Porter's Five Forces
- When detailed financial modeling is needed → use DCF or financial ratios

## Framework

```
IRON LAW: Relative Market Share, Not Absolute

The X-axis is RELATIVE market share = your share / largest competitor's share.
A company with 20% share in a market where the leader has 40% = 0.5x (Low).
A company with 20% share where the next largest has 10% = 2.0x (High).

NEVER use absolute market share. A 30% share means nothing without knowing
the leader's share.
```

```
IRON LAW: Plot THEN Strategize

Place ALL products/units on the matrix BEFORE deciding strategy.
Portfolio balance matters — a company with only Stars has a cash crisis
(Stars consume cash). A company with only Cash Cows has no growth pipeline.
```

### Step 1: Define the Portfolio Units

List all products, product lines, or business units to analyze. Each must be:
- A distinct unit with its own market and competitors
- Measurable in terms of revenue, market share, and market growth

### Step 2: Gather Data for Each Unit

For each unit, determine:
- **Market growth rate**: Annual growth rate of the total market (not your revenue growth). Typically, >10% = High growth.
- **Relative market share**: Your market share ÷ largest competitor's market share. >1.0x = High.

### Step 3: Plot on the Matrix

| | High Relative Market Share | Low Relative Market Share |
|---|---|---|
| **High Market Growth** | ⭐ **Stars** — High share in growing market. Generate revenue but consume cash to maintain position. | ❓ **Question Marks** — Low share in growing market. Need heavy investment to gain share, or divest. |
| **Low Market Growth** | 🐄 **Cash Cows** — High share in mature market. Generate surplus cash with low investment needed. | 🐕 **Dogs** — Low share in slow market. Minimal cash generation, limited potential. |

### Step 4: Determine Strategy per Quadrant

| Quadrant | Default Strategy | Nuance |
|----------|-----------------|--------|
| Stars | **Invest** to maintain/grow share | Will become Cash Cows as market matures |
| Cash Cows | **Harvest** — maximize cash extraction with minimal investment | Fund Stars and selected Question Marks |
| Question Marks | **Selective invest OR divest** — pick winners, cut losers | Most critical decision — not all can become Stars |
| Dogs | **Divest or reposition** | May keep if synergies with other units exist |

### Step 5: Assess Portfolio Balance

Check the overall portfolio health:
- **Healthy**: Mix of Cash Cows (funding) + Stars (growth) + 1-2 Question Marks (pipeline)
- **Unhealthy**: All Cash Cows (no growth), all Stars (cash drain), all Dogs (declining)

## Output Format

```markdown
# BCG Matrix Analysis: {Company/Portfolio}

## Portfolio Units

| Unit | Revenue | Market Growth | Rel. Market Share | Quadrant |
|------|---------|--------------|-------------------|----------|
| {Product A} | {$X} | {X%} | {X.Xx} | Star/Cash Cow/QM/Dog |

## BCG Matrix Placement

| | High Share (>1.0x) | Low Share (<1.0x) |
|---|---|---|
| **High Growth (>10%)** | ⭐ {list Stars} | ❓ {list Question Marks} |
| **Low Growth (<10%)** | 🐄 {list Cash Cows} | 🐕 {list Dogs} |

## Strategic Recommendations

### Stars — Invest
- {Product}: {specific investment recommendation}

### Cash Cows — Harvest
- {Product}: {how to maximize cash extraction}

### Question Marks — Decide
- {Product}: Invest / Divest — {rationale}

### Dogs — Divest/Reposition
- {Product}: {recommendation}

## Portfolio Health Assessment
{Overall balance evaluation and rebalancing recommendations}
```

## Examples

### Correct Application

**Scenario:** BCG for a Taiwanese electronics company with 4 product lines

| Unit | Market Growth | Rel. Share | Quadrant | Reasoning |
|------|-------------|-----------|----------|-----------|
| Laptop line | 3% | 1.8x (leader) | Cash Cow ✓ | Mature market, dominant position |
| Gaming peripherals | 18% | 0.4x | Question Mark ✓ | Fast-growing but small player |
| Server components | 12% | 1.2x | Star ✓ | Growing market, leading position |
| Feature phones | -2% | 0.3x | Dog ✓ | Declining market, minimal share |

**Strategy**: Harvest Laptop cash → fund Server (maintain Star) + selective invest in Gaming (Question Mark with potential). Divest Feature phones.

### Incorrect Application

**Scenario:** Same company

**What went wrong:**
- Used absolute market share (25%) instead of relative (25% / leader's 30% = 0.83x) → Would misclassify as High Share when it's actually Low. Violates Iron Law.
- Decided "invest in everything" without plotting first → No portfolio trade-off analysis. Violates Iron Law: plot then strategize.

## Gotchas

- **Market growth ≠ your revenue growth**: A product growing 20% in a market growing 25% is losing share. Use market growth rate, not company revenue growth.
- **Relative share threshold**: The 1.0x cutoff is a guideline. In fragmented markets with no clear leader, adjust the threshold. Document your reasoning.
- **BCG is a snapshot**: Markets evolve. Stars become Cash Cows, Question Marks become Dogs. Reassess annually.
- **BCG ignores synergies**: A "Dog" that provides key components to a "Star" may be worth keeping. Factor in cross-unit dependencies.
- **Not all Question Marks can be funded**: The hardest decision. Use additional criteria (market fit, team capability, strategic importance) to choose which to invest in.

## References

- For GE-McKinsey Matrix as an alternative (multi-factor version), see `references/ge-mckinsey.md`
- For comparison with other strategy frameworks, see `references/framework-comparison.md`