MKB1700 · Fundamentals Of Marketing
Buyer Behaviour
Buying is a process, not a moment. The consumer moves through five stages — need/want recognition, information search, evaluation of alternatives, purchase decision and post-purchase behaviour — and each stage is a chance for the marketer to intervene. That process runs inside a person shaped by four families of influence: cultural (culture, subculture, social class), social (reference groups, family, roles), personal (demographics, lifestyle/psychographics, personality) and psychological (motivation, perception, beliefs, learning). How much effort the buyer puts in is set by their involvement, which rises with perceived risk — itself the cost/sacrifice value type from Chapter 1. Businesses buy too: B2B buying is the same skeleton made more formal — derived demand, fewer larger buyers, a buying centre, and three buy classes (straight rebuy, modified rebuy, new task). Understand this and you know when and where to market — which is exactly what STP and the 7 Ps act on.
What this chapter covers
- 013.1 The five-stage consumer decision process
- 02The four information source types
- 03Cognitive dissonance (post-purchase doubt)
- 04The four influence families (cultural/social/personal/psychological)
- 05Roles in the buying group (initiator → payer)
- 063.2 Involvement & perceived risk
- 073.3 B2B buying — derived demand, buy classes, the buying centre
Worked example: walking a high-involvement buy through the five stages
- +1(a) Stage 1 — need recognition: a gap opens (the old laptop dies before exams), triggered by an internal or external stimulus.
- +1(a) Stages 2–3 — search & evaluation: the buyer gathers options from personal, public, commercial and experiential sources, then compares a choice set on evaluative criteria (price, battery, brand).
- +1(a) Stages 4–5 — purchase & post-purchase: buys the most-preferred option (unless derailed by stock-out or a friend's opinion), then judges satisfaction and spreads word of mouth.
- +1(b) High involvement: high price and high perceived risk → an extended decision process and wide search; a marketer lowers risk with reviews, warranties or free returns.
- +1(c) Post-purchase risk: cognitive dissonance — post-purchase doubt ('did I choose right?') that the unboxing email or follow-up is designed to soothe.
Key terms
- Consumer decision process
- The five stages a buyer moves through: need/want recognition, information search, evaluation of alternatives, purchase decision and post-purchase behaviour. Each stage is a point where the marketer can intervene.
- Cognitive dissonance
- Post-purchase doubt — the worry 'did I choose right?' after a buy, strongest for high-involvement purchases. Good marketers reassure buyers (follow-up, content, guarantees) to reduce it.
- Involvement
- How much effort, thought and risk a buyer attaches to a purchase, which sets how long and elaborate the decision process is. It rises with perceived risk; low-involvement buys win on availability and salience, high-involvement on information and reassurance.
- Derived demand
- The idea that business (B2B) demand ultimately flows from consumer demand — steel sells because people buy cars. It is one of the features that makes organisational buying different from consumer buying.
- Buy classes
- The three B2B buying situations: straight rebuy (routine reorder, minimal effort), modified rebuy (reorder with changed spec/terms, some review), and new task (first-time unfamiliar purchase, full search and negotiation).
Buyer Behaviour FAQ
What are the five stages of the consumer decision process?
Need/want recognition (a felt gap), information search (experiential, personal, commercial and public sources), evaluation of alternatives (comparing a choice set on evaluative criteria), purchase decision (picking the most-preferred option, or nothing), and post-purchase behaviour (satisfaction, word of mouth and managing cognitive dissonance). Each stage is a chance for the marketer to act.
What are the four influences on the buyer?
Cultural (culture, subculture, social class), social (reference groups, family, roles and status), personal (demographics, lifestyle/psychographics, personality and self-concept) and psychological (motivation, perception, beliefs and attitudes, learning). They run widest to narrowest, from the whole culture down to the individual's own mind.
What is the difference between high and low involvement?
Involvement is how much effort and risk a buyer attaches to a purchase. Low-involvement buys (chewing gum) are habitual or impulse with little thought — win on availability and salience. High-involvement buys (a car, a degree) trigger extended decision-making and wide search — win on information and reassurance. Perceived risk drives involvement up.
How is B2B buying different from consumer buying?
Same five-stage skeleton, but more formal: demand is derived (pulled by downstream consumer demand), there are fewer and larger buyers with longer relationships, professional buyers with formal criteria, and more people involved (a buying centre). It runs through three buy classes — straight rebuy, modified rebuy and new task — with a formal supplier review at the end.
Exam move
Make the five-stage process a backbone running left to right on your map, with the four influence families feeding into it and involvement as a label on how much of the process runs. Memorise the four information source types and which is most trusted (personal). Reuse two Chapter 1 nodes here for cheap cross-link marks: Maslow as the engine of motivation, and perceived risk as the cost/sacrifice value type. Place B2B as a parallel track joined by a labelled link ('same stages, more formal; demand is derived'). For the oral, be ready to defend why the mix is the 'marketing stimuli' that enters the search and evaluation stages.
