Improved the explanation

Author: javiereguiluz

reference/forms/types/language.rst

@@ -84,9 +84,13 @@ choice_self_translation
 
     The ``choice_self_translation`` option was introduced in Symfony 5.1.
 
+By default, the choice values are translated into the locale of the application.
+For example, when using ``en`` as the locale, you'll get an array like
+``[..., 'cs' => 'Czech', ..., 'es' => 'Spanish', ..., 'zh' => 'Chinese']``.
+
 If this option is ``true``, each choice value is translated into its own
-language instead of translating all of them into the current application locale
-(e.g. ``[..., 'cs' => 'čeština', 'es' => 'español', ..., 'zh' => '中文']``).
+language. The resulting array is the same regardless of the application locale:
+``[..., 'cs' => 'čeština', ..., 'es' => 'español', ..., 'zh' => '中文']``.
 
 .. include:: /reference/forms/types/options/choice_translation_locale.rst.inc