The four digits that recur in pro-commerce folklore are 1, 3, 6 and 8. They are not magic. They each describe a quality that the tradition reads as useful for a business that wants customers and revenue.
1 is the initiator. A name that resolves to 1 announces a category leader — first to market, definitional, the place customers go when they say “I need the best.” Risk: arrogance, monoculture, the kind of brand voice that wears out.
3 is the communicator. Resolving to 3 makes a brand inherently chatty and easy to remember; it markets itself through language. Risk: superficiality, fashion cycles, a brand that lives on the surface.
6 is the carer. A 6 brand is wholesome, family-oriented, easy to trust; think domestic products, hospitality, services for parents. Risk: blandness, saintliness, the inability to be edgy when an industry demands it.
8 is the executive. An 8 brand projects competence, scale, and adult money. The right number for financial services, premium goods, and anything where customers want to feel that the company is bigger than they are. Risk: coldness, the kind of brand that earns respect but no love.
The unlucky-for-commerce reputations attach mostly to 4 (too plodding for marketing-led industries), 7 (too withdrawn for a customer-facing role) and 9 (too saintly to charge properly). None of these is fatal. A 7 brand can sell beautifully to other 7s; a 9 brand can dominate ethical categories. The labels describe defaults, not destiny.