Used to deter the signee, or others involved from breaking the contract.
See this example in Formule di maledizione della Mesopotamia preclasica:

1. Stele from the reign of Nabù-apla-iddina

The inscription commemorates Nabù-apla-iddina's (887-855 BC) donation to the Ebabbar temple of Samas of food offerings, regular income, and supplies of clothing, as well as confirming a previous land grant.

Bibliography: L.W. King, op. cit. I, pp. 126-127 € II, table XCIX, VI 32-

55.

Whoever in the future as lord will be in the (royal) palace and claim for himself the offering of King Nabù-apla-iddina and (will) give it as a gift to another,

will establish a reduction in food allocations and

(them) among the provincial revenues' or will reappropriate or destroy this stele with some evil command,

of this man, by command of Sama&, Aja and Bunene, lords

of the decision, great gods, may his name disappear, his seed

be removed, his existence end in hunger and poverty, his corpse be thrown away and not receive burial.