Whats the most basic, yet crucial, component in an e-bikes charging system that, when faulty, can cause a catastrophic failure, and why do so many DIY repair enthusiasts insist on ignoring the fundamental principles of electrical engineering when attempting to fix it, despite the overwhelming evidence pointing to the importance of proper soldering techniques, insulation, and voltage regulation in preventing such failures, and can we really blame the manufacturers for not providing adequate documentation and support when the community itself seems so resistant to following established best practices and instead resorts to trial-and-error guesswork, which only serves to perpetuate the problem and create a culture of amateur hour tinkering that undermines the credibility of the entire e-bike industry?