A report is ḥasan li-dhātihi when a narrator has relatively lower memory precision and the other four conditions are present.
When the same report is transmitted through other chains and their support compensates for that lesser precision, it is called ṣaḥīḥ li-ghayrihi (صحیح لغیرہ). This compensation is termed talāfī (تلافی) here.
The other four conditions are trustworthy narrators, no omitted narrator, no hidden defect affecting soundness, and no trustworthy narrator's report contradicting a more reliable narrator.