If a party to a suit does not appear in the witness box to state their own case and does not offer themselves to be cross-examined by the other side, a presumption would arise that the case set up is not correct.

Civil Suit - If a party to a suit does not appear in the witness box to state their own case and does not offer themselves to be cross-examined by the other side, a presumption would arise that the case set up is not correct. (Para 12) 

Seethakathi Trust Madras v. Krishnaveni, 2022 LiveLaw (SC) 58 : AIR 2022 SC 558 : (2022) 3 SCC 150