That happiness which arises when the desired sense object comes in contact with the sense organs is indeed a thrill that is nectarine in the beginning. But, unfortunately, it vanishes as quickly as it comes, dumping the enjoyer into a pit of exhaustion and indeed into a sense of dissipation.
To explain: sense enjoyments arise only when the sense organs are actually in contact with the sense objects. This contact cannot be permanently established, for both the objects and the instruments that come in contact with the objects – the mind and intellect – are variable and changing. Also, the sense organs cannot enjoy the sense objects all the times with the same appetite, and even if they do so, the very object in the embrace of the sense organs withers and putrefies.
No individual can fully enjoy even the passing glitter of joy that the sense organs give, for even at the moment of enjoyment the ‘joy-possibility’ in it gets unfortunately tainted by an anxiety that it may leave him.
Hence, to a true thinker the temporary joys of sense are not at all satisfactory, since they only bury him in a tomb of sorrow. (Chapter 18 Verse 38)
Source – Holy Gita Ready Reference by Chinamaya International Foundation.