Canto 3 -
Araṇya-kāṇḍa
Chapter 47: Rāvaṇa Reveals his Identity to Sītā
Text 3.47.12

कामार्तस्तु महातेजाः पिता दशरथः स्वयम्।
कैकेय्याः प्रियकामार्थं तं रामं नाभ्यषेचयत्॥

kāmārtas tu mahā-tejāḥ pitā daśarathaḥ svayam
kaikeyyāḥ priya-kāmārthaṁ taṁ rāmaṁ nābhyaṣecayat

kāma-ārtaḥ tu = in pain due to passion [and so]; mahā-tejāḥ = who possessed great prowess; pitā = His father; daśarathaḥ = Daśaratha; svayam = was personally; kaikeyyāḥ = Kaikeyī; priya-kāma-artham = in order to fulfill his desire to please; tam rāmam = Śrī Rāma; na = not; abhyaṣecayat = he did coronate.

His father Daśaratha, who possessed great prowess, was personally in pain due to passion [and so] he did not coronate Śrī Rāma in order to fulfill his desire to please Kaikeyī.1

Lord Rāma’s father did not want to coronate Lord Rāma without Kaikeyī’s approval. Kāmārtaḥ (“in pain due to passion”) expresses the reason for [Daśaratha’s] first promise [to Kaikeyī when he said], “I will make you happy.” Having promised thus, he became incapable of breaking his promise when she sought a boon to have Śrī Rāma exiled, and [therefore] he didn’t coronate Rāmacandra.

1 Rāmāyaṇa-bhūṣaṇa: priya-kāmārtham iti. priya-karaṇa-kāmāya pratijñāta-kaikeyī-priya-karaṇa-nirvāhāyety arthaḥ.