There is a wide range of quality out there in the audio world. Some audios are quite effective and helpful, and some are not. Popularity is not necessarily a good indicator of quality and effectiveness. I strongly recommend researching the credentials first of anyone whose audios you want to listen to. There are numerous audios out there created by people who do not have proper training (or any training at all) and who are not using effective hypnotic suggestions in their audios. Some of the affirmations and hypnotic suggestions in amateur audios can result in reinforcement of negative thoughts, emotions, behaviors and habits. If you're listening to random audios on YouTube or other websites created by unknown people, you could potentially be unwittingly exposing yourself to subliminal messages that you may not approve of. Personally, I won't allow anyone I don't know and trust to access or influence my subconscious mind, and I recommend you don't either.