Agree, Bruno. Some visual examples that might help:
Highly consistent — the same design and visual elements repeated with little/no variation. As a whole, my subjective judgement is that it has coherence but there’s not much freedom or character expressed.
These are coherent — they belong together, but the consistency of details is looser. Consistency of an inner black unites the cups to the bowls, reinforced by the common textures and forms. More character is present.
Consistent finish, limited consistency otherwise. But a very coherent set of items.*
I’d add that depending on your audience and what you’re trying to achieve, your use of consistency might need to be more or less pronounced. There’s no perfect, universal balance.