Why doesn't the `default` value work in mongoose schema when nothing was entered?
<p>This is my Schema and the image <code>default</code> value doesn't seem to work when I leave the HTML input field empty before submitting a "blog" post. </p>

<pre><code>var blogSchema = new mongoose.Schema({
    title: String,
    image: {
        type: String,
        default: "some image url"
    },
    body: String,
    created: {
        type: Date,
        default: Date.now
    }
});
</code></pre>

<p>this is the input that is going into the database.</p>

<pre><code>{ __v: 0,
  title: '',
  body: '',
  _id: 583af591c460fca539b8f787,
  created: 2016-11-27T15:02:41.613Z,
  image: '' }
</code></pre>

<p>I don't understand what the problem is since the <code>image</code> doesnt have any value and it isn't setting the default value.</p>