<p>From my part (since it was I who did this), you had answered the question already on the duplicate.  </p>

<p>Since you effectively had recognised that the question was a duplicate and had correctly answered on the correct question, my role was simple - to play the janitor and thus cleanup by removing the answer.</p>

<p>There was no reason to merge here since you had already answered the question.</p>

<hr>

<p>Most traffic to Stack Exchange sites is via search engines.  To redirect users to the correct question, Stack Exchange uses the policy of redirection as explained here:</p>

<ul>
<li><a href="http://meta.stackexchange.com/questions/125220/automatically-redirect-anonymous-user-from-unanswered-duplicate-question-to-corr">Automatically redirect anonymous user from unanswered duplicate question to corresponding answered version</a></li>
</ul>

<p>Now ordinarily I would normally leave questions and answers alone unless they start to receive high traffic (visits).  In this case, you had answered the question on the duplicate - thus leaving two answers on separate questions would have been nonsensical - you potentially would be benefiting twice with the same answer.  </p>

<p>Hence the janitorial rule here applies - cleanup and move on to find similar stuff to tidy up.</p>