Question: what is the main concern of the job characteristics model
[{'answer': 'enriching jobs in organizational settings', 'provenance': [{'wikipedia_id': '40826054', 'title': 'Job characteristic theory', 'start_paragraph_id': 1, 'start_character': 105, 'end_paragraph_id': 1, 'end_character': 146, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '40826054', 'title': 'Job characteristic theory', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 566, 'bleu_score': 0.9731482306711111, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7751461048638483771}, 'section': 'Section::::Abstract.'}]}]