Sometimes vairāgya is translated as detachment. But this is not precise enough. Because reality is non-dual, you are the very connection of everything, so there is no detachment, no detachment—that is dual.

Why is objectivity towards sense objects necessary? The initial reaction of the mind and senses to the world is often emotional: everything encountered is met with rāga (preference, attraction) or dveṣa (repulsion, aversion, hostility), a degree of sympathy or antipathy (a pleasurable or dissatisfying form of desire). All desires arise from a sense of smallness and disconnection from everything else. This produces emotion, movement in the mind – all emotions are positive or negative forms of love. Because they are expressions of love, such mental and sensory reactions must be handled carefully, otherwise they will dominate the person. When I am controlled by emotion, by passion, I am not available for vicāra, meaningful inquiry.

This doesn't mean I shouldn't enjoy objects, but I know (!) that pursuing the satisfaction of sensory pleasure has a downside, a loss. If I connect with an object out of blind passion, I am bound; this is called a binding desire. What we want is non-binding desire. Controlled enjoyment, knowing that there is always the pitfall of creating an unconscious trace (vāsanā), which will later manifest as an urge in my mind.

Other forms of loss are: I become karmically responsible for the situation that causes my action. I therefore become mentally dependent, or addicted. Desire blinds me, and I no longer see the possibilities, losing wisdom and emotional maturity. My inner silence is disturbed, and I can't enjoy myself. I get angry when I don't get what I want. Oh my god, etc., etc. :).

Whether or not I will enjoy the sense object is also very fickle. It depends on three things:

1. Availability or proximity of the object (obvious, because what if there's a scarcity? Or my partner isn't available for sex?). This is called viṣaya lābha (object acquisition or availability) or viṣaya sannidhāna (proximity to the object).

2. Availability of the sense to enjoy the object (if I have a cold, I suddenly lose my sense of taste. If I have libido problems, I can no longer enjoy my partner). This is called indriya sāmarthya (the capacity for sensory functioning) or indriya śakti (the power of sensory functioning).

3. Availability of my mind to enjoy the object (confusion can arise, such as being automatically triggered by a food smell, but my mind being too agitated by another object to enjoy it. Or my otherwise desirable partner is seducing me, but now I'm preoccupied because I'm binge-watching). This is called manas prasāda (serenity of mind) or citta avyākulatā (non-agitated mind).

Who wants to live in that inner turbulence? Sufficient objectivity towards objects is necessary to properly hear and assimilate the teaching. The value or this capacity, this attitude, this state of mind is mentioned in Bhagavad Gītā 13.9 as the tenth of a series of twenty conditions/qualifications/attitudes (values) for freedom.