Lying to yourself leads to failure.
Experiments where people could cheat on a test and found that cheaters not only deceive themselves, but are largely oblivious to their own lies. Their ruse is so potent that they’ll continue to overestimate their abilities in the future, even if they suffer for it. Cheaters continue to prosper in their own heads, even if they fail in reality.
Fortunately, this research also found “that self-deception diminishes over time only when self-deceivers are repeatedly confronted with evidence of their true ability.
REFERENCES
The Slow Decay and Quick Revival of Self-deception, by researchers Zoë Chance, Francesca Gino, Michael I. Norton, Dan Ariely