The black box model considers the buyer's response as a result of a conscious, rational decision process, in which it is assumed that the buyer has recognized a problem, and seeks to solve it through a commercial purchase. In practice some purchase decisions, such as those made routinely or habitually, are not driven by a strong sense of problem-solving. Such decisions are termed "low-involvement" and are characterized by relatively low levels of information search and evaluation activities. In contrast, "high involvement" decisions require a serious investment of time and effort in the search and evaluation process. Low involvement products are typically those that carry low levels of economic or psycho-social risk. High involvement products are those that carry higher levels of risk and are often expensive, infrequent purchases. Regardless of whether the consumer faces a high or low involvement purchase, he or she needs to work through a number of distinct stages of a decision process.