Brand promise is the collective experience people have with your brand once you combine all other factors of your brand foundation. So it's not tactical or directive. It's the essence of the brand.
Brand Building Fundamentals: Positioning
Brand Building Fundamentals: Desired Consumer Experience
Brand Building Fundamentals: Brand Personality
Brands can be fun, free willed, playful, studious, a work horse, etc. But those attributes don't drive much energy into the brand. Worse, your interpretation of "fun" may be decidedly different than mine. So we could work on the same brand using "fun" as the brand personality and end up in vastly different areas.
Branding Should Be Logical
Build Private Label Brands That Last
Consumers have been trained to perceive three tiers in most retail environments: cheap stuff, expensive stuff and everything else. However, owned brands can fall prey to presenting too many layers. Some retailers have difficulty killing off weak products or collections that no longer match the brand and instead create sub-tiers and super-tiers. When consumers can’t distinguish the nuances, they apply the three-tier rule for simplicity.