Groupthink

The popularity of the Nazi government was evidenced by them being elected into power in Germany, yet to say that the Nazi government was the preferred party of Germany would be an example of Argumentum_ad_populum.

Similarly, when Top Gear test cars to define the best in category, they are really identifying that which satisfies the chosen criteria, normally that which is supposed to appeal to the majority of the audience. However, mass censuses on opinions about cars are not carried out hourly, thus we cannot know what the majority of the population will think is best.