This may seem obvious but it is a bias that is commonly overlooked. People turning to consultants will often seek their advice from someone with a very small set of experiences which serves as a means by which the resulting recommendations are likely drawn. In a way, this is effectively the buyer preselecting the desired outcome and choosing a consultant that will deliver the desired outcome. An example of this would be choosing a network engineer to design a solution when that engineer only knows one product line; naturally the engineer will almost certainly design a solution from that product line. In choosing someone with limited experience in that area we are, for all intents and purposes, directly the results by picking based on a strong bias. This happens extremely often in IT, presumably because those hiring consultants base this decision on what they think are foregone conclusions about what the resulting advice will be and forgetting to step back and get advice at a higher level.