Not everyone purge immediately. It comes when it comes.
Often, especially when one drinks the plant medicine later on, the purge will occur.
However, you can experience wonderful deep processes without purging.
One person vomits, another has a few toilet visits, yawns, trembles or effortlessly takes a “deep dive” into his/her inner world with stillness and concentration.

Physical surrender, through whatever form, is a way of surrender to yourself. You allow and create space to have a deeper inner process journey.