Why does he always have to lie about everything?

He lies because his followers don't research or read widely. So, he can. And they believe him.

He lies because he is a narcissist. Narcissists lie to win (by their own definition of winning). Everything is an opportunity to win. Therefore, everything and every moment is an opportunity to lie.

Narcissists are like addicts. That old saying-- How do you know when an addict is lying? When their lips are moving -- applies to narcissists.

every time he opens his mouth, a lie comes out.
And his disciples don't bother to fact check what he says or tweets.
And if you show them the facts, they just call them "fake news".
This is such a shit show.... I can't wrap my head around the ignorance of those who follow him, and who believe blindly that everything he says is true.
Even if there is FOOTAGE and actual PROOF of him saying or doing what he says he didn't do or say.

Apparently he does.

this...
People with narcissistic personality disorder (NPD) are characterized by the personality traits of persistent grandiosity, an excessive need for admiration, and a personal disdain and lack of empathy for other people.[7][8] As such, the person with NPD usually displays arrogance and a distorted sense of personal superiority, and seeks to establish abusive power and control over others.[9] Self-confidence (a strong sense of self) is a personality trait different from the traits of narcissistic personality disorder; thus, people with NPD typically value themselves over others, to the extent of openly disregarding the wishes and feelings of anyone else, and expect to be treated as superior, regardless of their actual status or achievements.[7][10] Socially, the person with narcissistic personality disorder usually exhibits a fragile ego (self-concept), intolerance of criticism, and a tendency to belittle other people, in order to validate their own superiority.[10]

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5, 2013) indicates that a person with NPD possesses at least five of the following nine criteria, typically without possessing the commensurate personal qualities or accomplishments for which they demand respect and status:

Has a grandiose sense of self-importance (e.g.exaggerates achievements and talents, expects to be recognized as superior without commensurate achievements).
Is preoccupied with fantasies of unlimited success, power, brilliance, beauty, or ideal love.
Believes that he or she is "special" and unique and can only be understood by, or should associate with, other special or high-status people (or institutions).
Requires excessive admiration.
Has a sense of entitlement (i.e., unreasonable expectations of especially favorable treatment or automatic compliance with his or her expectations).
Is interpersonally exploitative (i.e., takes advantage of others to achieve his or her own ends).
Lacks empathy: is unwilling to recognize or identify with the feelings and needs of others.
Is often envious of others or believes that others are envious of him or her.
Shows arrogant, haughty behaviors or attitudes.[7][10]
Narcissistic personality disorder usually develops either in adolescence or in early adulthood,[7] and it is common for children and adolescents to display personality traits that resemble NPD, but such occurrences are usually transient, and register below the clinical criteria for a formal diagnosis of NPD.[10] True symptoms of NPD are pervasive, apparent in varied social situations, and are rigidly consistent over time. Severe symptoms of NPD can significantly impair the person's mental capabilities to develop meaningful human relationships, such as friendship, kinship, and marriage. Generally, the symptoms of NPD also impair the person's psychological abilities to function socially, either at work, or at school, or within important societal settings. The DSM-5 indicates that, in order to qualify as symptomatic of NPD, the person's manifested personality traits must substantially differ from the cultural norms of society.[7]

Associated features[edit]
People with NPD exaggerate their skills, accomplishments, and their degree of intimacy with people they consider high-status. Such a sense of personal superiority may cause them to monopolize conversations,[10] or to become impatient and disdainful when other persons talk about themselves.[7] When wounded in the ego, either by a real or a perceived criticism, the narcissist's displays of anger can be disproportionate to the nature of the criticism suffered;[10] but typically, the actions and responses of the NPD person are deliberate and calculated.[7] Despite occasional flare-ups of personal insecurity, the inflated self-concept of the NPD person is primarily stable.[7]

To the extent that people are pathologically narcissistic, the person with NPD can be a self-absorbed control freak who passes blame and is intolerant of contradictory views and opinions; is apathetic towards the emotional, mental, and psychological needs of other people; and is indifferent to the negative effects of his or her behaviors, whilst insisting that people should see him or her as an ideal person.[7] To protect their fragile self-concept, narcissists use psycho-social strategies, such as the tendency to devalue and derogate and to insult and blame other people, usually with anger and hostility towards people's responses to the narcissist's anti-social conduct.[11] Because their fragile egos are hypersensitive to perceived criticism or defeat, people with NPD are prone to feelings of shame, humiliation, and worthlessness over minor incidents of daily life and imagined, personal slights,[10] and usually mask such feelings from people, either by way of feigned humility, or by responding with outbursts of rage and defiance, or by seeking revenge.[7][8] The merging of the inflated self-concept and the actual self is evident in the grandiosity component of narcissistic personality disorder; also inherent to that psychological process are the defense mechanisms of idealization and devaluation and of denial.[12]

The DSM-5 indicates that: "Many highly successful individuals display personality traits that might be considered narcissistic. Only when these traits are inflexible, maladaptive, and persisting, and cause significant functional impairment or subjective distress, do they constitute narcissistic personality disorder."[7] Given the high-function sociability associated with narcissism, some people with NPD might not view such a diagnosis as a functional impairment to their lives.[13] Although overconfidence tends to make people with NPD very ambitious, such a mindset does not necessarily lead to professional high achievement and success, because they refuse to take risks, in order to avoid failure or the appearance of failure.[7][8] Moreover, the psychological inability to tolerate disagreement, contradiction, and criticism, make it difficult for persons with NPD to work cooperatively or to maintain long-term, professional relationships with superiors and colleagues.[14]

Deep down I think he knows he sucks and is trying to prove to everyone that he doesn't

I agree with a lot of what you say...but on this..I don't.  I think that "he thinks" he is the greatest person to ever walk the earth.  The way he talks about how things were a mess before he took over and his constant "I did this...I did that".  I really do think he has in his mind that he is superior to all.  

Blech!!

It’s who he is. He’s a liar, among other things.

Because if you lie, you don’t have to do any preparation or any work you just say whatever the heck you want to say and if you say the exact opposite tomorrow who cares just lie more. It’s just easier to keep lying and lying then you don’t have to look up, learn or remember anything you just blurt our whatever is in your brain. Easy peasy

Lol, there is a website that tracks his golfing.

#winningatoutgolfingObama


www.trumpgolfcount.com/

Lying is easy in the moment.

Being factual, thoughtful, articulate, and accountable is hard.

And lying has worked for him this far in life; he’s not going to stop now.