静态变量默认初始化与代码初始化

Question

如果我没有在代码中初始化count变量，而是让其默认值初始化，那么我的代码将正确显示count = 1。 但是，如果我在代码中将其初始化为0-> private static int count = 0，它将显示0。请问任何一个原因是什么？

class Singleton3 {
    private final static Singleton3 obj = new Singleton3();
    private static int count;

    private Singleton3() {
        count++;
    }

    public static Singleton3 getInstance() {
        return obj;
    }

    public static int getCount() {
        return count;
    }
}

public class SingletonImplEagerInitialization {
    public static void main(String[] args) {
        Singleton3.getInstance();
        Singleton3.getInstance();
        Singleton3.getInstance();
        Singleton3.getInstance();
        Singleton3.getInstance();
        System.out.println("count: " + Singleton3.getCount());

    }
}