更好地理解任务和调度

我是一个新手在任务，并行和调度等。这里我创建了两个blockingcollection。一个用来收集输入，另一个用来收集输出。我添加了100项。所以我认为它们的总数应该是100或0。或者它们的和等于100。

然而我发现它们都是0。请用简单的语言帮助我理解这些概念。

    static void Main(string[] args)
    {
        new Program().run();
    }
    void run()
    {
        int threadCount = 4;
        Task[] workers = new Task[threadCount];
        Task.Factory.StartNew(consumer);
        // We can do other work in parallel
        for (int i = 0; i < threadCount; ++i)
        {
            int workerId = i;
            Task task = new Task(() => worker(workerId));
            workers[i] = task;
            task.Start();
        }
        for (int i = 0; i < 100; ++i)
        {
            Console.WriteLine("Queueing work item {0}", i);
            inputQueue.Add(i);
            Thread.Sleep(50);
        }
        Console.WriteLine("Stopping adding.");
        inputQueue.CompleteAdding();
        Console.WriteLine("The count in InputQueue= {0}", inputQueue.Count);// 0
        Task.WaitAll(workers);
        outputQueue.CompleteAdding();
        Console.WriteLine("The count in OutputQueue= {0}", outputQueue.Count); // 0
        Console.WriteLine("Done.");
        Console.ReadLine();
    }
    void worker(int workerId)
    {
        Console.WriteLine("Worker {0} is starting.", workerId);
        foreach (var workItem in inputQueue.GetConsumingEnumerable())
        {
            Console.WriteLine("Worker {0} is processing item {1}", workerId, workItem);
            Thread.Sleep(100);          // Simulate work.
            outputQueue.Add(workItem);  // Output completed item.
        }
        Console.WriteLine("Worker {0} is stopping.", workerId);
    }
    void consumer()
    {
        Console.WriteLine("Consumer is starting.");
        foreach (var workItem in outputQueue.GetConsumingEnumerable())
        {
            Console.WriteLine("Consumer is using item {0}", workItem);
            Thread.Sleep(25);
        }
        Console.WriteLine("Consumer is finished.");
    }
    BlockingCollection<int> inputQueue = new BlockingCollection<int>();
    BlockingCollection<int> outputQueue = new BlockingCollection<int>();
}