Yogasūtra I.30 - vyādhi-styāna-saṁśaya-pramāda-ālasya-avirati-bhrāntidarśana-alabdhabhūmikatva-anavasthitatvāni citta-vikṣepāḥ-te-antarāyāḥ

What, if any are the obstacles?

There are nine types of obstacles to reaching the state of Yoga. These are illness, mental stagnation, doubt, lack of foresight, laziness, overindulgence, distorted perception, lack of perseverance and regression. They are obstacles because they create mental disturbances and encourage distractions.

The more vulnerable we are to these interruptions, the more difficult it is to reach the state of Yoga.