Self deception is not uncommon. The human mind is capable of many things in search for a place to hide from fears and pains.

Some people can even just "say" they believe, to make themselves feel better, knowing its not true, but thinking it raises them in the others opinion. Its called "hypocristy" and abounds in todays world

Not for me...but I know some people who, I'm sure start to then actually progress on to believing their own lies

Hmmmm ... No. To state a belief in something, to support or defend a belief, doesn't mean it is actually believed. There is, valued by them, a pay-off for pretending to believe.

Risk-takers don't believe that there is no risk, although they may say as much. They just value the experience, or social admiration, often just in-the-moment, above the possible negative consequences.

Smokers don't really believe that what they're doing is harmless, to themselves or others, and imposes no cost to themselves and their community (healthcare services and funds). They focus on the value of their right to self-determination, and enjoyment in-the-moment. They will still declare: "I've been smoking for 30 years, I'm as fit as; it hasn't done me any harm.". (Heard said at their mother's wake; who died of a stroke, due to a lifetime of smoking.)

Even fear of nothingness, doesn't make one a believer in something unbelievable, deliberately. It provides no comfort, because it is disbelieved. It is the delusion, an actual belief, that provides comfort.

Distinct from this, declaring a belief provides great benefits of inclusion, perceived superiority, support against feared nothingness etc; and, defence against self-questioning (of values, ethics and behaviours), defence against admitting "I don't know", and defence against inability to explain morals and opinions held and espoused. Homosexuality is sinful (makes me feel uncomfortable) because ... " ... my god said so, in my book-of-right & wrong, that he dictated to some men".

An absolute, delusional, belief that one has been talking with god, or that god speaks through one's religious leaders, may be comforting; but, it's dangerous to mental health and consequently, to societal stability.
Anyway, that's how I see believers versus deliberate fear-filled fakers.

Many people seem to prefer a pretty lie to the ugly truth even when they know better.

Belief in something with no evidence

I've been studying the human characteristics of self confidence and self esteem. They are the holy grail of personality traits needed dating. People who have them can't explain how they obtained them, and people who lack them can't obtain them without assistance from others.

After reading many published articles, I have come to the conclusion that people need to believe in themselves, and people who aren't blessed with success have no alternative than to try to believe something for which there is no evidence.

Plenty of evidence for human self deception...look at the Aussie PM and what he "wants to believe". Hilarious...Morrison still has not yet noticed he asked for rain, and got fire.

The mind is a creative force.

Its possible but my modus operandi is usually just to avoid thinking about it then i don't have to believe anything.

Deliberately means with intent. It is an active process and if someone wants something enough they will believe it, critical thinking be damned.

"Devotion is a tool to dissolve yourself into what you are doing" - Sri Sadhguru

It depends on your definition of "believe" I suppose. True belief in my view can't be chosen. It can be forced (including on oneself) but as skado points out, there will be cognitive dissonance that will tend to increase over time. In other words belief is a product of what you've experienced and what you know and if your beliefs diverge from that, at the expense of some energy you can allow that divergence, but it will become increasingly difficult to ignore the resulting difficulties.

For example, my first wife developed very serious mental illness and the relationship became toxic and abusive. But I had been taught that one's marriage was specially protected and blessed by god and by submitting the relationship to him in faith, things would improve. Besides, divorce was taboo. I was also taught that secular mental health care would lead her further from god and thereby undermine god's work in her life, whereas religious counseling would work much better (it didn't).

The upshot of all this is that sure I believed what I was taught, but it extended a marriage that arguably shouldn't have lasted 5 years, to 15 years. What broke through the denial represented by my beliefs was waking up one night with my wife standing over me in a trance-like state with a butcher knife. That, and my then 14-year-old daughter begging me to get her out of there. At that point, I finally started acting to protect my children and myself, and in our rational self-interest generally. But as soon as I did that, it was impossible for me to continue to "believe" that god supported the "sanctity" of our marriage or that god or his book or his people had ever given me good advice in this regard.

One could ask rhetorically whether I truly "believed" to begin with. I would respond that I wanted to believe because my entire self worth had been constructed around living in a way I imagined was pleasing to god. Contrary data that suggested this was not working was seen as temptation and deception of various kinds. I would say that my current belief that religious faith generally and Christianity specifically are failed epistemologies that lead strongly away from, rather than toward, truth, is FAR more a settled and confident belief than my former beliefs to the contrary. But then religious faith is often very much about holding out hope when all hope is lost, and fearing being doctrinally wrong or losing one's identify as a member of the RIGHTeous, was greater than the fear of being factually wrong.

Their motto (and this is a Bible verse) is, "let god be true and every man a liar".

In other words, force yourself to believe without -- and, if necessary, contrary to -- evidence.

Yes, but not without creating eddies of dissonance.

Yup

Absolutely. We do it all the time. It’s called suspension of reality and we mostly engage with when reading or watching TV.

When we do it in real life, and it is impacting upon our functionality it may be worth being circumspect about what we are buying into.