title: How can I better learn to "not pay for what you don't use"?
body: <p>I've just gotten answers to <a href="https://stackoverflow.com/q/28299581/1593077">this question</a> which, at the bottom line, tell me: "Doing X doesn't make sense since it would make you pay for things you might not use."</p>
  
  <p>I find this maxim difficult to follow; my instincts lean more towards seeing what I consider clear semantics, with things defined "in their place". More generally, it's not immediate for me to realize what the <a href="http://wiki.uqm.stack.nl/Druuge" rel="nofollow noreferrer">hidden costs and secret tariffs</a> would be for a particular design choice?.</p>
  
  <p>Is this covered by (non-reference) books on C++? Is there someplace relevant online to better enlighten myself on following this principle?</p>