"In the hard sciences, research is reasonably reliable because it measures things. In the soft (social) sciences, research is often not about measuring things, but about asking questions.
"In other words, rather than watching to see if you’re cheating on your wife, they ask you if you are. Then they treat your answer as a fact rather than just the bullshit it is.
"The consequence of this is that a great many of the surveys, reports, and studies we read tell us nothing about what we’re trying to understand, they tell us what people say about what we’re trying to understand. A very different thing."Source: Marketers Are From Mars, Consumers Are From New Jersey