The Associated Press conducted a probe using court testimonies, interviews and over 4,000 entry forms of people heading to Syria in 2013 and 2014 to join the religious fundamentalists. They found Daesh candidates to be "overwhelmingly ignorant" of Islam and reported that visiting Imams and indoctrination videos were implemented to compensate.
Some 70% of new adherents had "basic knowledge" of sharia law, with 24% claiming "intermediate" familiarity and 5% saying their understanding was "advanced." West Point's Combating Terrorism Center published a study saying that the less versed a fundamentalist was, the more likely they were to carry out suicide bombings, suggesting that they viewed extreme action as a substitute for doctrinal proficiency.
Some reported being taken aback and regretful about their their experience with Daesh, with one European former member saying, "I realized that I was in the wrong place when they began to ask me questions on these forms like 'When you die, who should we call?'" A former CIA Middle East extremist expert remarked that this kind of thinking is typical of many Daesh recruits from the West, who join to receive "a sense of belonging, a sense of notoriety, a sense of excitement…Religion is an afterthought."