Final answer:
Products high in experiential qualities are the most difficult to evaluate, as buyers often have imperfect information about these intangible aspects before purchasing, leading to hesitation and challenges within the market.
Step-by-step explanation:
In the context of evaluation, products that are the most difficult to evaluate are those high in experiential qualities. These are aspects of a product which buyers are less than 100% certain about, due to their intangible nature. In situations where information about the quality of products is highly imperfect, such as with complex services or high-technology goods, markets may face difficulties. This is because buyers might not be able to accurately determine the product's quality before purchase, and hence, may be hesitant to engage in transactions. At the same time, sellers with high-quality products might find it challenging to convince potential buyers of their product's worth, leading to a market where goods are undervalued and imperfect information hinders trade.