In-situe interviews can range from short 10 minute interviews, to 2 minute polls. Researchers often use in-situe interviews also to observe consumer behaviour, as behaviour is often different to what people say they do when indirectly interviewed. In one study for example, we approached patrons in bars and restuarants who were consuming the client's product or their targeted competitor's products. Patrons were asked why they chose to consume that particular drink, and their perceptions of other competing products. Researchers used observational check lists to note the behaviour of partrons before approaching them.
Responses are unaffected ny memory loss as in the case where they are interviewed after the event.
Researchers can also observe actual behaviour, and get a feeling for the environment in which the products or services are used.