Yōga Sūtra 2.07

सुखानुशयी रागः।

sukhānuśayī rāgaḥ।

[सुख अनुशयी रागः।
sukha = pleasure; anuśayī = stems from the experience of; rāgaḥ = passion;]

Passion stems from the experience of pleasure.

The urge to experience pleasure is passion. The passion that is so much glorified as necessary attribute for success in material world is an obstacle in the path of Yōga.