Why does ordering a table by a column containing links fail?

I use DataTables to paginate and order a table containing user data.

The first column contains links instead of plain text. It seems that for this reason, the ascending/descending ordering is wrong (random).

It seems that the presence of diacritics on the Name column is also part of the ordering issue.

  <h2>Data Tables</h2>
  <table id="employees" class="table table-striped">
    <thead>
        <tr>
            <th>Name</th>
            <th>Position</th>
            <th>Office</th>
            <th>Age</th>
            <th>Start date</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td><a href="#">Tiger Nixon</a></td>
            <td>System Architect</td>
            <td>Edinburgh</td>
            <td>61</td>
            <td>2011-04-25</td>
        </tr>
        <tr>
            <td><a href="#">Garrett Winters</a></td>
            <td>Accountant</td>
            <td>Tokyo</td>
            <td>63</td>
            <td>2011-07-25</td>
        </tr>
        <tr>
            <td><a href="#">Ashton Cox</a></td>
            <td>Junior Technical Author</td>
            <td>San Francisco</td>
            <td>66</td>
            <td>2009-01-12</td>
        </tr>
        <tr>
            <td><a href="#">Cedric Kelly</a></td>
            <td>Senior Javascript Developer</td>
            <td>Edinburgh</td>
            <td>22</td>
            <td>2012-03-29</td>
        </tr>
        <tr>
            <td><a href="#">Ștefan Popa</a></td>
            <td>Accountant</td>
            <td>Tokyo</td>
            <td>33</td>
            <td>2008-11-28</td>
        </tr>
        <tr>
            <td><a href="#">Brielle Williamson</a></td>
            <td>Integration Specialist</td>
            <td>New York</td>
            <td>61</td>
            <td>2012-12-02</td>
        </tr>
        <tr>
            <td><a href="#">Herrod Chandler</a></td>
            <td>Sales Assistant</td>
            <td>San Francisco</td>
            <td>59</td>
            <td>2012-08-06</td>
        </tr>
        <tr>
            <td><a href="#">Rhona Davidson</a></td>
            <td>Integration Specialist</td>
            <td>Tokyo</td>
            <td>55</td>
            <td>2010-10-14</td>
        </tr>
        <tr>
            <td><a href="#">Colleen Hurst</a></td>
            <td>Javascript Developer</td>
            <td>San Francisco</td>
            <td>39</td>
            <td>2009-09-15</td>
        </tr>
        <tr>
            <td><a href="#">Sonya Frost</a></td>
            <td>Software Engineer</td>
            <td>Edinburgh</td>
            <td>23</td>
            <td>2008-12-13</td>
        </tr>
    </tbody>
</table>

new DataTable('#employees', {
    info: false,
    filter: false,
    paging: true,
    "aLengthMenu": [5, 10, 25, 50, 100],
    initComplete: function() {
        if (this.api().page.info().pages < 2) {
            $('.dt-paging').hide();
        }
    }
});

1. What is my mistake?
2. What is the easiest, most reliable fix for this issue?