Scientists have been studying how the brain learns and creates memories for short-term and long-term storage, and how the information is organized for efficient processing. They have shown that the hippocampus stores specific experiences while the Neocortex generalizes across experiences. Essentially, when our brain processes an experience some of its synapses grow stronger while others grow weaker. This pattern of synapses strength is what forms the memory.
Now if the brain were to take every experience and create a new pattern for each one, then learning would not really take place, rather we would just have a memory full of experiences. But in its efficiency the brain fits new experiences, to the extent that it can, into existing patterns. These patterns are successful patterns. The more experience can fit a pattern of better the pattern is. One could generalize across behavioral patterns in the same way. If we didn't have a mechanism to evaluate behavioral patterns, then we would be unable to differentiate a successful behavior from an unsuccessful behavior. This ability helps us develop knowledge and beliefs.
The more frequent the experience the stronger the pattern। The stronger the pattern, the deeper the knowledge and belief around that knowledge. The brain becomes less willing to create a new pattern, because the existing pattern has been imprinted as successful.
This makes it easier to understand why a manager who was so full of new ideas when he or she first took a new role, now seems unwilling to even listen to ideas about change. The manager's brain has become so impatterned with a belief about the successful way the department works, that it rejects patterns which vary from that belief.