Ex-Muslims are individuals who were raised as Muslims or converted to Islam and later chose to leave the religion. These individuals may encounter challenges related to the conditions and history of Islam, Islamic culture and jurisprudence, as well as local Muslim culture. In response, ex-Muslims have formed literary and social movements, as well as mutual support networks and organizations, to address the difficulties associated with leaving Islam and to raise awareness of human rights issues they may face.

According to Pauha and Aghaee (2018), apart from context and additional levels of struggle, the deconversion process and some of the reasons for leaving religion might not be much different for Muslims leaving their religion compared to Christians leaving theirs. According to Simon Cottee (2015), the intellectual process of leaving religion begins with the onset of doubt about Islam and its practice. In Islamic tradition, doubts about the religion are generally severely reprimanded with threats of hell in the afterlife toward impressionable young children and associating doubting individuals with possession by devils and further superstitious practices of exorcism. Therefore, doubt tends to be significantly discouraged, ranging from bad-mouthing about those who raise any doubts to brutally punishing them. This builds up peer and community pressure not to doubt and deviate from the status quo, leading to unsettling fears that someone whose doubts would be revealed might be put to shame and further banishment. The next steps for doubters are self-censorship and attempts to suppress recurring thoughts, leading to frustration.

Simon Cottee (2015) wrote that it is very difficult for Muslims to express doubts and questions about Islam. Those who get the opportunity, must conduct self-search on the Internet, and if they wish to ask questions to any religious expert, then they have to do so with a lot of caution to avoid accusations of disbelief; rather than asking why God said something in the scriptures, they need to rephrase their inquiry in religiously 'right' language, asking what God meant by something. In other cases, doubters use real or imaginary proxies to avoid hostility towards themselves. Since many doubts are not answered, the unintended consequence is a further level of dissatisfaction. Cottee says ex-Muslims focus their doubts mostly on the truth claims of Islam, and the utility and morality of Islamic commands or prohibitions.

Phil Zuckerman summarizes Cottee's points about types of doubts engaged by ex-Muslims on the path of leaving Islam, namely: epistemological, moral, and instrumental doubts, as well as forms of doubts such as significant personal experiences, exposure to alternatives, scriptural discoveries, spiritual alienation, political events, etc. Epistemological doubts question the existence of God in several ways, such as through the problem of evil, by looking at injustice and misery around the world, which allegedly would not have existed if there really had been a good God. They also question the Islamic creation myth with respect to the theory of evolution, and the contradictions between the concepts of free will and predestination. Moral doubts concern issues such as the unequal treatment of women in Islam, and why non-Muslim children or good non-Muslims go to hell according to Islamic theology. Instrumental doubts question the utility and morality of Islamic commands or prohibitions, such as the prohibition of artistic representation of living beings (see Aniconism in Islam), which doubters claim hamper freedom of artistic expressions such as drawing, photography, sports like chess, music, etc. (see also Muslim women in sport), in turn, hampers individual growth and social-cultural participation.

Cottee's study indicates that ex-Muslims start feeling that they are betraying their true self and also deceiving their loved ones in the process, leading to feelings of shame for their own continued closeted pretending and subsequent feelings of isolation and loneliness. On the one hand, ex-Muslims often opt to reduce commitment to social relationships that require pretending to be Muslim; on the other hand, they often do not have the freedom to choose the kind of social relationships they prefer, thus exacerbating their social isolation and loneliness further. Cottee outlines different phases on the way of leaving Islam: disavowal of self, relief, excitement, guilt, anger, residual anxiety, confusion, disclosure, and more.

The 2007 Khalil Bilici study stated that motivations for leaving Islam can be broadly classified into two categories, namely intellectual/ideological motivations and social/experiential motivations. According to Teemu Pauha and Atefeh Aghaee (2018), the first group would find religion to be naive and irrational, whereas second group emphasizes the constraints and breaches of human rights of individuals negatively affecting social progress as their most significant concern. Pauha and Aghaee further point out that, depending on the doubting group one belongs to, one may find religion to be an example of stupidity or viciousness.

Findings of the Khalil Bilici study state that among ex-Muslims with intellectual/ideological motivations, the following ones seem important:

Cottee's interviewees inform their intellectual doubts about perceived religious inconsistencies in Islam like, the barbarism of certain verses in the Qur'an, the improbability of the existence of God, the wickedness of the possibility of God creating Hell, discontent with the treatment of women, and more.