Php array striping out html -

if dont use implode html tags dont show. why? should use in array not incur?

if( get_field('additional_specifications') ) {     while ( have_rows('additional_specifications') ) : the_row();     $addspec[] = '<tr><td>' . get_sub_field('spec_name') . '</td><td>' . get_sub_field('spec_value') . '</td></tr>';   endwhile;     $spec= implode($addspec);  $content .=  $spec;  }  if ($content) { echo '<table class="spec-table">',$content,'</table>'; } 

if( get_field('additional_specifications') ) {     while ( have_rows('additional_specifications') ) : the_row();         $content .= '<tr><td>' . get_sub_field('spec_name') . '</td><td>' . get_sub_field('spec_value') . '</td></tr>';  endwhile;  }  if ($content) {     echo '<table class="spec-table">'. $content .'</table>';  }  ?>