* If there is a transaction and it is rolled back, then the callback is cancelled.
* Callbacks must commit any transactions that they begin.
*
- * This is useful for updates to different systems or separate transactions are needed.
+ * This is useful for updates to different systems or when separate transactions are needed.
+ * For example, one might want to enqueue jobs into a system outside the database, but only
+ * after the database is updated so that the jobs will see the data when they actually run.
* It can also be used for updates that easily cause deadlocks if locks are held too long.
*
* @param Closure $callback
* Callbacks must not start nor commit any transactions.
*
* This is useful for updates that easily cause deadlocks if locks are held too long
- * but where atomicity is strongly desired for these and some related updates.
+ * but where atomicity is strongly desired for these updates and some related updates.
*
* @param Closure $callback
* @since 1.22