Bhagavad Gita · Akshara Brahma YogaChapter 8, Shloka 14 (8.14)

Shankaracharya — "satata" and "nityaśaḥ". Satatam iti nairantaryam ucyate, nityaśaḥ iti dīrgha-kālatvam ucyate, na ṣaṇ-māsaṃ saṃvatsaraṃ vā kiṃ tarhi yāvaj-jīvaṃ — "satata" means without a break, "nityashah" means for a long time — not six months or a year, but throughout life; sulabhaḥ sukhena labhyaḥ.

Acharya Ramanuja — the Lord himself chooses. Atyarthaṃ mat-priyatvena mat-smṛtyā vinā ātma-dhāraṇam alabhamāno niratiśaya-priyāṃ smṛtiṃ yaḥ karoti — the one who, out of intense love for me, cannot even survive without remembering me; tasya … ahaṃ sulabhaḥ, aham eva prāpyaḥ na mad-bhāva aiśvaryādikaḥ — for him I myself am the goal, not sovereign power and the like. And most beautiful of all: tad-viyogam asahamānaḥ aham eva taṃ vṛṇe — because I cannot bear separation from him, I myself choose him; mat-prāpty-anuguṇopāsana-vipākaṃ tad-virodhi-nirasanam atyarthaṃ mat-priyatvādikaṃ ca aham eva dadāmi — the ripening of worship, the removal of obstacles, and love — it is I who give them. Evidence: Mundaka 3.2.3 (yam evaiṣa vṛṇute tena labhyaḥ), Gita 10.10–10.11.

The difference: Shankara — being easy to reach is the fruit of unbroken practice; Ramanuja — it is the Lord's grace: he himself chooses the devotee and gives the means.