What is the purpose of examining inferior criminal-court records in revision under BNSS section 438?

Section 438(1) lets the High Court or a Sessions Judge call for the record of an inferior criminal court "for the purpose of satisfying itself or himself as to the correctness, legality or propriety of any finding, sentence or order" and "as to the regularity of any proceedings". It is a supervisory power, not a rehearing as of right or a retrial on demand, and section 403 bars altering or reviewing a signed judgment except to correct a clerical or arithmetical error.