The first of these is a too heavy reliance on general terms, a fault especially common among salespeople who have only a general knowledge of their products and those of their competitors. One of the resulting problems of having only general product knowledge is that it does not at all serve customers who seek the kind of information they need to make the best buying decision. Customers enter our stores already having general product knowledge. They cannot be expected to put their confidence in a salesperson whose product knowledge is more or less the same as theirs. Moreover, customers rarely buy from a salesperson in whom they have little confidence.
Confidence means trust.
The two are inter-related. Once customers do not trust the salesperson's product knowledge, they tend to doubt the salesperson's honesty. Because everyone has doubts about the intentions of salespeople who are not qualified to do what they say they'd like to do for us. That is, help us make the best purchase decision. A second problem with having only general product knowledge is linked to the truism that confidence begets confidence.