title: Why do I need to provide NG_VALUE_ACCESSOR at the component level?
body: <p>Take a look at this example:</p>
  
  <p><a href="https://stackblitz.com/edit/angular-nxjeu3" rel="noreferrer">https://stackblitz.com/edit/angular-nxjeu3</a></p>
  
  <p>It does not work.</p>
  
  <p>But if I move the <code>providers</code> from the <code>@NgModule</code> to <code>HelloComponent</code>, it does work. Why? Shouldn't providing at the <code>@NgModule</code> level or <code>@Component</code> level be the same?</p>