A method declared on the parent that only one subclass overrides or invokes; the parent's interface includes a method that does not apply to most instances the agent reasons about.
The method lives on the subclass that uses it; reading the parent's interface returns only the methods every instance supports, dropping the irrelevant declaration from the agent's window.
Before the refactoring
class Employee {quota() { /* used only by Salesperson */ }}
After the refactoring
class Salesperson extends Employee {quota() { /* ... */ }}
The parent's interface is muddied with subclass-specific methods; the agent can't tell which methods apply to which subclass without inspecting usage.
If the parent occasionally consults the method for type checks or polymorphic dispatch, pushing it down forces awkward downcasts at every consumer the agent must verify.
The parent's interface shrinks by one method; queries about any subclass's behavior load fewer irrelevant declarations into the window, and code generated against the parent's interface no longer references a method most instances do not support.
Pushing down a method that callers reach through a parent-typed reference forces every such call site to downcast first; each downcast is a runtime type check the agent's generated code has to handle at every consumer.