Strategic Business Leader · Competitive forces

Industry Life Cycle and Competitive Forces for ACCA SBL

Updated 11 October 2026 · Fact-checked

The industry life cycle shows an industry moving through introduction, growth, maturity and decline. At each stage, the strength of Porter's five forces and the best strategy change. To answer an SBL question, identify the stage from the scenario evidence, assess each force, then recommend strategies that fit that stage.

Understand Industry Life Cycle and Competitive Forces

An industry life cycle describes how an industry's demand and profit pattern changes over time. The usual stages are introduction, growth, maturity (sometimes with a shake-out before it) and decline. It is a model, not a law. Industries do not all follow it, stages can last very different lengths, and firms can change the curve through innovation.

The link to competitive forces is the key exam skill. Porter's five forces (threat of new entrants, supplier power, buyer power, substitutes, rivalry) are not fixed. Their strength shifts as the industry ages. So a five forces analysis is only a snapshot of one stage, and the right strategy depends on the stage.

In introduction, demand is small and customers are unsure. Few firms compete, so rivalry is low. But costs are high, technology is uncertain and losses are common. Entry barriers may come from technology or know-how. Strategy focuses on building awareness, setting standards and winning early adopters.

In growth, demand rises fast. Rivalry is often modest because the market is expanding and firms can grow without taking share. New entrants are attracted by the growth. Strategy focuses on capturing share, building brand, widening the range and adding capacity.

In maturity, growth slows and demand is mainly replacement. Rivalry rises as firms fight for share, often on price. Buyers are experienced and powerful, and weaker firms are squeezed out. Strategy focuses on cost reduction, differentiation, segmentation and defending share. In decline, demand falls because of substitutes or changing tastes. Rivalry can be intense if exit barriers are high and capacity is excess. Strategy choices include leadership, niche, harvest or divest.

Key rules to remember

Industry life cycle stages: Introduction → Growth → Maturity → Decline; Some versions add a shake-out between growth and maturity. Use the stages the scenario supports.
Porter's five forces: New entrants + Supplier power + Buyer power + Substitutes + Rivalry; Assess each force at the current stage. Say whether it is rising or falling over time.
Typical rivalry pattern: Low in introduction → moderate in growth → high in maturity → high or varied in decline; This is a general tendency, not a rule. Decline rivalry depends on exit barriers and spare capacity.
Decline strategies: Leadership | Niche | Harvest | Divest; Choose by the strength of your position and how attractive the remaining demand is.

How to solve Industry Life Cycle and Competitive Forces questions

Use this method for any SBL question on how an industry's stage affects competition and strategy.

1Read the requirement. Note whether it asks for the stage, the forces, the strategies or all three.
2Find evidence in the scenario for the stage: sales growth, number of competitors, product standardisation, price trends, profit levels and capacity.
3State the stage you conclude and give your reasons. If the evidence is mixed, say so.
4Assess each relevant force at this stage. Give the scenario fact, then say whether the force is strong or weak.
5Explain how the forces are likely to change as the industry moves to the next stage.
6Recommend strategies that fit the stage and the company's position, such as cost leadership, differentiation, niche, harvest or divest.
7Link each strategy to a force it addresses, and note risks or limits of the model.
8Finish with a clear conclusion or recommendation in the format asked, such as a report or briefing note.

Quickest way: Stage, forces, strategy in three lines

When to use it: Use this when time is short, or when the task carries few marks and needs a short, focused answer.

Name the stage and give two pieces of scenario evidence.
Pick the two or three forces that matter most now and say how strong each is.
Give two strategies that fit the stage and say which force each one tackles.
Add one sentence on how the position may change at the next stage.

Common mistakes in Industry Life Cycle and Competitive Forces

Listing textbook features of each stage without using the scenario.
Students memorise the model and write it out as theory.
Fix: Start every point with a scenario fact. Then apply the model to that fact.
Treating the life cycle as a fixed law that every industry follows.
The diagram looks neat and certain.
Fix: Say it is a guide. Note that innovation, new uses and market changes can extend or reshape the curve.
Saying rivalry is always high in maturity and always low in growth.
Students learn the pattern as a rule.
Fix: Describe it as a tendency. Check the scenario for exit barriers, capacity, concentration and differentiation.
Doing a five forces analysis with no link to the stage.
Students treat the two models as separate topics.
Fix: For each force, say how it differs now compared with earlier or later stages.
Recommending a strategy that does not fit the company's position.
Students give generic advice such as 'invest heavily'.
Fix: Match the strategy to the stage and to the firm's strengths. For decline, justify leadership, niche, harvest or divest from the evidence.
Confusing the industry life cycle with the product life cycle.
The stage names are the same.
Fix: Remember that the industry covers all firms and products in a sector. A single product's cycle can be shorter or different.

Worked examples

Example 1

Zentra Ltd makes electric scooters. Industry sales have grown steadily for five years, but the rate of growth is now slowing. Many new firms entered in the last three years. Prices are falling and customers compare models online. Identify the stage and explain how two competitive forces are affecting Zentra. (10 marks)

Show the solution

Stage: slowing growth, many entrants, falling prices and informed buyers point to the late growth or early maturity stage, possibly with a shake-out coming.
Rivalry: with many firms and slowing growth, firms can no longer grow without taking share from rivals. Falling prices show rivalry is increasing. Zentra may face price competition and pressure on margins.
Buyer power: customers compare models online, so they have better information and low switching costs. This raises buyer power and adds to the pressure on prices.
Likely change: if growth slows further, weaker firms may exit and rivalry may focus on cost and differentiation.
Strategy link: Zentra should reduce unit costs and differentiate, for example by range, service or brand, to protect margins.

Answer: The industry is moving from late growth towards maturity. Rivalry and buyer power are both rising, which squeezes prices. Zentra should focus on cost efficiency and differentiation, and be ready for a shake-out.

Example 2

Brightwell plc sells printed directories. Demand has fallen each year because customers use online search. Brightwell has specialised printing plant that has no other use. Advise the board on strategy in this declining industry. (10 marks)

Show the solution

Stage: falling demand caused by a substitute (online search) shows the industry is in decline.
Forces: the threat of substitutes is very strong. Rivalry may be intense because specialised plant creates high exit barriers, so firms stay and compete for shrinking demand.
Option 1, leadership: only suitable if Brightwell can become the main survivor and gain share as others leave. This needs investment in a shrinking market, so it is risky.
Option 2, niche: focus on segments where print remains valued, such as local business or older customers, and charge a premium.
Option 3, harvest: cut investment and marketing, maximise cash from existing customers and run down the plant.
Option 4, divest: sell early while the business still has value. The specialised plant limits buyers, so the price may be low.
Recommendation: a niche or harvest approach fits best, because the substitute is strong and the plant has no other use. Consider digital products to move out of the declining industry.

Answer: The industry is in decline, driven by a strong substitute and high exit barriers. Brightwell should pursue a niche or harvest strategy, avoid heavy investment, and look at digital offerings as a longer-term move.

Exam tips

Always state the stage you have chosen and give scenario evidence. Marks go to application, not to listing the model.
Say how forces change over time. This shows analysis and earns professional skills marks.
In decline questions, name the four options (leadership, niche, harvest, divest) and justify one from the facts.
Mention limits of the model. Industries can be rejuvenated, and stages are hard to identify in real time.
Use the format asked, such as a briefing note, and keep your recommendation clear and commercial.

Practice questions from Competitive forces

Industry Life Cycle and Competitive Forces in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Industry Life Cycle and Competitive Forces: frequently asked questions

What are the stages of the industry life cycle?

The usual stages are introduction, growth, maturity and decline. Some versions add a shake-out before maturity. Each stage has a different pattern of demand, competition and profit.

How do competitive forces change over the industry life cycle?

Rivalry tends to be lower in introduction and growth and higher in maturity, as growth slows and firms fight for share. Threat of entry is often highest in growth. Buyer power and substitutes tend to matter more later. This is a pattern, so always check the scenario.

What strategies suit a mature or declining industry?

In maturity, firms focus on cost reduction, differentiation, segmentation and defending share. In decline, the options are leadership, niche, harvest or divest. The best choice depends on the firm's position and exit barriers.

Is the industry life cycle the same as the product life cycle?

No. The industry life cycle covers a whole sector. The product life cycle covers one product or brand, and it can be shorter or follow a different pattern.