Add (rough) causality

wiki/src/donate.html

@@ -695,7 +695,7 @@ permitted by law.</strong></p>
       </li>
       <li class="gray">
         <div class="key-label">Administration and fundraising</div><div class="key-percent">(17%)</div>
-	<p>We make the most of the money that we receive. We prefer spending
+	<p>We make the most of the money that we receive because we prefer spending
 	our time improving Tails for our users.</p>
       </li>
     </ul>