Of two Italian restaurants at a street corner, both bustling with people, which would you pick? A large one with 50 items on its menu, including pizza, pasta, risotto and lasagna, or a small one with just 6 items, all pizzas?
The answer, of course, depends on what you are looking for. If you crave for regular Italian cuisine, you should pick the large restaurant. The food there is likely to be pretty good, and indistinguishable from most other successful Italian restaurants in your city.
If you want a different experience, head to the pizzeria. Since its owners have committed to make just these 6 pizzas, they cannot afford to have them taste like regular pizzas. Their competitors across the street already serve those and 44 other dishes. They would need to make their 6 pizzas unique. And when you eat them, you would either love them or hate them – there is no room for middle ground.
Businesses with smaller menu cards are usually the ones that stand apart.