I have the following cast:

```
int myInteger = (int)myItem.EnumValue;

```

Where the enum is:

```
public enum EnumValue
{
     Yes= 0,
     No = 1
}

```

From my observations it seems that when the EnumValue on myItem is not set, the value of EnumValue is on default set to Yes and subsequently cast to 0. 

Why is the enum not null? Is my observation correct and why is it so?