Patterns and Repetitiveness

Sometimes I find a piece of fanfiction where an author introduces a new factor to an existing setting. For example, a new element of harmony. Then this new factors change the chain of events. But often authors prefer to stick to known events too much, even when the new factors can prevent some canon events from happening and create brand new events instead. So to stick to canon events new characters suddenly become dumb, lose powers and can't do anything. What a shame.

Two new factors:

Source.