From Brand as Context in Interaction Design:
Designers need to understand the subtle difference between creating consistency and creating coherency… It is better to strive for coherency, where the consistency… is married with a system of meaning that people can believe in and choose to be a part of: the brand.
And…
If we’re not careful, we can sometimes force ourselves to follow a process that, while it gives us comfort, can also remove the moments where we get to explore… nuances, and try to create something with which people can form an even deeper bond.
Good. Stuff.