The single greatest technical challenge facing quantum computing is quantum decoherence and error rates. Qubits—the fundamental units of quantum information—are extremely sensitive to external environmental disturbances such as temperature fluctuations, electromagnetic interference, and physical vibrations. These disruptions cause qubits to lose their quantum state rapidly, resulting in calculation errors. Building fault-tolerant, scalable quantum computers requires complex error-correcting codes that demand vast numbers of physical qubits to sustain a single reliable logical qubit, presenting a massive engineering hurdle.