Why would an entity's sequence based ID differ from the database current sequence value in EAP 6?

Issue

• An entity class identifier is declared as follows

      ...
      @Id
      @GeneratedValue(strategy=GenerationType.SEQUENCE, generator="EVENT_SEQ_GEN")
      @SequenceGenerator(name="EVENT_SEQ_GEN", sequenceName="EVENT_SEQ")
      ...
  

  • At the time an instance of the entity class is created, the value of an Oracle sequence (EVENT_SEQ) in the database is 55
  • During insert of the instance, the ID value automatically populated is different from the sequence value (e.g. 51 or 2753)
• How does the SEQUENCE generation strategy work?
• What is the impact of the hibernate.id.new_generator_mappings property?