Mystery and exclusivity are two very powerful human motivators. Let's take one at a time.
A partial reveal is always more powerful than a full reveal. And the more often one is exposed to the partial reveal, the more one craves the full reveal. It's human nature. Whether it is in a new product unveiling or a television series plot line, people get hooked based on the mystery and not knowing. I have witnessed many successful new product introductions in which outdoor advertising reveals a little bit at a time in each subsequent iteration until the buzz reaches a very high level. In dating, playing "hard to get" is often a very successful strategy.
Which leads to exclusivity. If a brand is only available in certain places, especially a limited number of upscale places, it usually has significantly more cache. For instance, if you can only purchase the brand on Rodeo Drive in Beverly Hills, Upper Fifth Avenue in New York, Hong Kong's Causeway Bay, New Bond Street in London, Champs Elysees in Paris, Orchard Road in Singapore or The Mall at Short Hills in New Jersey, then your brand likely has significant luxury cache.
A brand is even more exclusive if the vast majority of people in developed countries have never even heard of it. Such a brand can serve as a badge to inner circle members. These brands might be found in enclaves such as Aspen (Colorado), Costa Smeralda (Sardinia), Côte d’Azur (France), Monaco, Northeast Harbor (Maine), St. Moritz (Switzerland) and Yellowstone Club (Montana).
Sometimes being mysterious and playing "hard to get" creates even more demand. Some brands might want to choose this strategy.
In case you are wondering, the image at the top of this blog post is of a Maybach Exelero. It's a very nice car with a top speed of 218 mph. You can purchase one for $7.8 million.