[mcphage]

Methods can be split into private methods. But what that sometimes means is, when you're trying to understand how a piece of information flows through a method to fix a bug, instead of it being all self-contained in the method, instead you have to jump around to 10 places in a file to see where the information goes. That severely increases the cognitive overhead.

[robmcm]

There is also a cognitive overhead when trying to find local variables defined in huge functions, at least when they are split into smaller private (static) methods (with variables passed as arguments) it's easier to track.

Both in the parent method and in the encapsulated child.