Can you explain how you could have altered the member variable before you changed it to private? Not sure how this works

A way that Craig could have appeared to change the value of mCharacterName from the Example class would be:

PezDispenser.java

public class PezDispenser {
    public String mCharacterName = "Yoda";

}

Example.java

public class Example {

    public static void main(String[] args) {
        System.out.println("We are making a new pez dispenser");
        PezDispenser dispenser = new PezDispenser();
        System.out.println("The pez dispenser is going to be: " + dispenser.mCharacterName);

        dispenser.mCharacterName = "Batman"; // LINE 8

        System.out.println("The pez dispenser is going to be: " + dispenser.mCharacterName); 
    }
}

Any code that prints out the value of mCharacterName, that comes after line 8 in the Example class, would appear as "Batman"

But since the String literal of "Yoda" is assigned to mCharacterName, that means any code that logs the value of mCharacterName to the screen before line 8 would still appear as "Yoda" because that's mCharacterName's assigned value in the PezDispenser class.

OUTPUT:

We are making a new pez dispenser
The pez dispenser is going to be: Yoda
The pez dispenser is going to be: Batman

Craig doesn't want the chance of this ever being a possibility, if we were to compile Example.java and inside of the PezDispenser class, mCharacterName was set to private, the Example class wouldn't compile.