I have always been fascinated with personality typology. The Myers Briggs model, DISC, 9 types, Jungian archetypes and other models help us to discover our strengths, weaknesses and also importantly learn about other people with different preferences. We are all different and this is what makes us interesting.
Brands are also like people and need their own personality. A brand cannot be every personality type at the same time. A brand is also very rarely going to appeal to everyone at the same time. Take Apple vs Microsoft, totally different personalities.
A brand needs to stand for something and not have multiple personality disorder.