title: BASH: IF / ELIF incorrect triggering
body: <p>I need not just an answer for the following situation, but an explanation please.
  There are 2 files - NEW and OLD:</p>
  
  <pre><code>touch NEW ; 
  touch -t $(date -d '3 week ago' +%Y%m%d%H%M) OLD
  </code></pre>
  
  <p>Now i'm making the script to output different messages according to the results of comparison of a NEW file to the old one:</p>
  
  <pre><code>#!/bin/bash                                                                                                           
  if [[ "NEW" -ot "OLD" ]]                                                          
          then echo "file is old"                                                                                       
  elif [[ "NEW" -nt "OLD" ]]                                                        
          then echo "file is new"                                                                                       
  fi
  </code></pre>
  
  <p>But no matter which condition is correct, "file is old" will always be printed.</p>
  
  <p>The same situation with IF ELSE FI statement. </p>
  
  <p>File Information:</p>
  
  <pre><code>    stat NEW
    File: 'NEW'
    Size: 0               Blocks: 0          IO Block: 4096   regular empty file
  Device: fd05h/64773d    Inode: 3227449730  Links: 1
  Access: (0644/-rw-r--r--)  Uid: (48935/ UNKNOWN)   Gid: (48935/ UNKNOWN)
  Access: 2017-06-02 20:53:27.461237303 +0000
  Modify: 2017-06-02 20:53:27.461237303 +0000
  Change: 2017-06-02 20:53:27.461237303 +0000
   Birth: -
  
  stat OLD
    File: 'OLD'
    Size: 0               Blocks: 0          IO Block: 4096   regular empty file
  Device: fd05h/64773d    Inode: 3227452336  Links: 1
  Access: (0777/-rwxrwxrwx)  Uid: (48935/ UNKNOWN)   Gid: (48935/ UNKNOWN)
  Access: 2017-06-02 20:29:05.607617334 +0000
  Modify: 2017-05-12 20:20:00.000000000 +0000
  Change: 2017-06-02 20:23:42.872363548 +0000
   Birth: -
  </code></pre>
  
  <p>Where am i wrong?</p>