How does a quantum computer actually execute an algorithm if measurement destroys the quantum state?

[CMPunk96]

This confuses me. Every explanation says measuring a qubit destroys its quantum state. But you need to measure results to know if the algorithm worked. How does that work?

[NicholasCleverley]

Great observation. The trick is you don't measure until the end. The quantum computation runs with qubits in superposition throughout. Only at the final step do you measure