title: Is executePendingTransactions() always necessary?
body: <p>This is more of a theoretical question.</p>
  
  <p>I have a situation where my app crashes on a fragment swap with an <code>executePendingTransactions()</code> call and works fine without it.</p>
  
  <p>My question is what could go wrong in general if i don't call <code>executePendingTransactions()</code>?</p>
  
  <p>As i understand, without this method a <code>Fragment</code> swap may not happen immediately, although i have never experienced this. </p>