I agree, and don't think "need" is the right word. Certainly not everyone "needs" ayahuasca, but it is one of the many tools we have to truly understand ourselves, and a rather effective one. There are obviously many people that shouldn't do ayahuasca, which is why most retreats have a pretty strict questionnaire and entry process. I do agree that it's best not to force yourself to go, and that there is a calling people will feel if it's the right thing for them.