No, Quantum Computers Can't Do Everything Faster

The most persistent myths about quantum computing — and the clearer picture that replaces them

Quantum computing has a mythology problem. A decade of overpromised timelines and misreported breakthroughs has left the public with a warped picture of what the technology actually does. Let's fix that.

Myth 1: Quantum computers are just faster classical computers

This is the most common misunderstanding. Quantum computers aren't universally faster — they're differently powerful. For many everyday tasks (word processing, web browsing, playing videos), a quantum computer would perform identically to a classical one, or worse. Quantum advantage is specific: it applies to problems with particular mathematical structures — search problems, simulation of quantum systems, certain optimisation problems, and factoring.

Myth 2: Quantum computers will break all encryption immediately

Shor's algorithm theoretically breaks RSA encryption — but requires a fault-tolerant quantum computer with millions of stable logical qubits. Today's best machines have hundreds of noisy physical qubits. The gap is enormous. Post-quantum cryptography migration is genuinely important, but the threat is a decade away at minimum.

Myth 3: Whoever builds the most qubits wins

Qubit count is one metric among many, and often a misleading one. A 1,000-qubit machine with 1% error rates is far less useful than a 50-qubit machine with 0.01% error rates. Coherence time, gate fidelity, connectivity, and error correction overhead matter as much as raw qubit numbers.