In an interview with Brendan Eich, creator of the first version of JavaScript, the distinguished software engineer revealed that the worst parts of the language were actually borne out of delusions caused by a bleed in his brain. While working on the Netscape Navigator browser in May 1995, the engineer famously spent ten consecutive days cranking out the initial prototype. Unbeknownst to Eich, a massive aneurysm he suffered while creating the language coincided with major architectural decisions - the consequences of which the JavaScript community still suffers from to this day.
Eich described how - up until the injury occurred - he initially planned for JavaScript to feature typing, classical inheritance, and block scoping, among a host of normative language elements. As history shows, none of these survived the injury. On the afternoon of the third day developing the language, an artery near his prefrontal cortex ruptured without warning, and growing intracranial pressure quickly caused the engineer to enter a delusional state. From the outside, Eich appeared to be relatively normal, working diligently on the exciting new experimental language. However, anyone realizing the degree to which he was tearing up the language and injecting wholly demented ideas would quickly have identified his descent into utter madness.
As the pressure inside his head gradually increased, Eich detailed how he became more and more unhinged with his design decisions. By the start of the fourth day, he had straight-up ditched classical inheritance in favor of prototypal. By the sixth day, his grip on reality had weakened to the degree that hoisting, different flavors of equality, the concept of being "truthy", and variable execution contexts when evaluating the "this" keyword all seemed like good ideas. Eich's mental condition progressively worsened through to the tenth day, which is when his eminently disturbed mind concocted the grotesque interplay between [], and various arithmetic operators.
Upon completing the language and presenting his work to the team, Marc Andreessen had Eich immediately rushed to the nearest hospital, where he was treated and made a full recovery. The company, though, was stuck with the mutilated language while Eich recovered, and was forced to ship it with the next release of Netscape Navigator. The rest, is history.