Obstacles to the Goal
Prāpya-virōdhi ('obstacles to the prāpya/goal') refers to factors that impede the attainment or full realization of the goal — the state of eternal kaiṅkarya (service to the Lord) in Vaikuṇṭha. While upāya-virōdhi obstructs the means (prapatti), prāpya-virōdhi obstructs the arrival at and full enjoyment of the goal itself.
The Goal and Its Obstacles
The goal (prāpya) in Sri Vaishnava theology is not merely liberation from saṃsāra but the positive state of eternal kaiṅkarya in Vaikuṇṭha — serving the Lord with a fully expanded dharma-bhūta-jñāna, in the company of the nitya-sūrīs and fellow muktas, in unending bliss. Obstacles to this goal include: (1) attachments to the fruits of action that keep one bound to lower goals; (2) desire for kaivalya (mere isolation/self-centered liberation) rather than Vaikuṇṭha-kaiṅkarya; (3) failure to cultivate bhāgavata-sambandha (association with devotees) which purifies and accelerates the path to the goal.
Virōdhi Texts
The virōdhi texts (obstacles) in Sri Vaishnava literature cover both upāya and prāpya virōdhis. The complete understanding allows the prapanna to conduct their post-prapatti life in a way that removes obstacles and aligns increasingly with the goal. This is not anxiety-driven (the protection is already guaranteed by prapatti) but a loving response to the Lord's invitation.
Bhāgavata-Aparādha as Key Prāpya Obstacle
Piḷḷai Lokācārya identifies offense to devotees (bhāgavata-aparādha) as a particularly serious prāpya-virōdhi: it damages the bhāgavata-sambandha that is itself the path and the environment for reaching the goal. The prapanna who offends fellow devotees is undermining the very context that makes the goal realizable.