Matsya Purana — The Dialogue of Kacha and Devayani: Dharma
ततः कच न ते विद्या सिद्धिमेषा गमिष्यति //
tataḥ kaca na te vidyā siddhimeṣā gamiṣyati //
Therefore, O Kaca, this knowledge will not attain fulfillment (success) for you.
This verse does not speak about pralaya directly; it focuses on vidyā (sacred knowledge) and the conditions under which it becomes siddhi (effective attainment).
It implies a broader dharmic principle applicable to rulers and householders: learning or counsel is fruitful only when supported by right conduct, restraint, and proper adherence to instruction—otherwise even correct knowledge fails to yield results.
No explicit vastu or ritual procedure is stated; the takeaway is methodological—technical knowledge (including ritual or architectural śāstra) becomes successful only when properly learned and correctly applied.