124 The Marketing Book
act in question. And behavioural intentions
usually correlate highly with the performance of
the behaviour itself.
Fishbein and Ajzen refer to this approach to
the prediction of behavioural intentions as the
Theory of Reasoned Action. Ajzen (1985) has
proposed a second theory, the Theory of Plan-
ned Behaviour, which incorporates an addi-
tional determinant of intention. This is perceived
behavioural control, or the individual’s belief that
he succeeds in the task in hand. Bagozzi and
Warshaw (1990) have proposed a Theory of
Trying in which past behaviour is taken into
consideration as a means of predicting future
choice. A full discussion of these approaches is
available in Foxall (1997).
Post-decisional evaluation
Another filtering device determines the extent
to which consumers quickly put their intentions
into practice, shown in Figure 6.1 as ‘impeding
and facilitating conditions’. These are the situa-
tional variables, such as access to funds or credit,
availability of compatible products, social
acceptability, that determine whether a partic-
ular purchase will take place or not. No amount
of strong intention will guarantee purchase in
the absence of these and a hundred other
facilitating conditions. Purchasing also depends
on past behaviour. It would be absurd and naive
to suppose that a consumer who had just bought
a video recorder based on an obsolete system
could simply go through the above decision
process and make another, more lasting, pur-
chase a week later.
But the consumer decision process does not
end when a purchase has been made. Most
important of all from a marketing viewpoint is
whether the consumer will buy the selected
brand again on a later purchase occasion. The
first purchase of a brand – or even the first few
purchases – can be considered no more than a
trial by the consumer. The clearest indication of
whether it is worth buying again comes from its
evaluation in use (Ehrenberg, 1988). Something
that often needs to be resolved in the case of
expensive, infrequently bought items such as
consumer durables is the cognitive dissonance
or feeling of mental unease that follows their
purchase. Cognitive dissonance arises when
two contradictory beliefs are held at the same
time: ‘I have spent so much on this car and my
neighbour tells me his gets from 0 to 60 mph a
second faster!’ People tend to try to reduce
dissonance by dropping one or other of the
opposing beliefs or by emphasizing one at the
expense of the other. The car purchaser might
well conclude, therefore, that his car was more
prestigious since it had cost more or had a more
auspicious marque. Or that his car was guaran-
teed for longer, or ran unleaded fuel, or needed
less frequent services. Some advertising is
deliberately geared to the needs of the dissonant
consumer who has recently purchased;
although they are less obvious than they used to
be, ads for cars still sometimes stress the
performance characteristics of the advertised
and competing makes.Selectivity
We have seen that a frequent assumption in
consumer research has been that consumer
decision making must be a uniform process for
all consumers. Once the stages outlined above
had been identified, it was common for
researchers and managers to expect all con-
sumers to pass through them in a similar
fashion on each purchase occasion. Yet both
common sense and our experience as con-
sumers suggests that not all transactions are
preceded by this entire process of cognitive
learning. Both personal and situational factors
often intervene at one or other stage to throw
the procedure off course or to circumvent it
totally.
A striking characteristic of consumer deci-
sion making is the selectivity it entails. Con-
sumers are not exposed to all of the stimuli that
might conceivably influence them; their atten-
tional and perceptual processes are highly
selective in what they admit and consider.
Memory processes are similarly limited since