Quantum non-demolition measurement in multi-qubit transmon processors is compromised at low to moderate measurement drive amplitudes due to Landau-Zener transitions. These transitions occur when multiple photons interact with the transmon, causing it to jump multiple energy levels. Researchers have demonstrated that this phenomenon is consistent with experimental observations, shedding light on the limitations of dispersive readout in circuit QED. The loss of quantum non-demolition character has significant implications for quantum computing, as it can lead to errors and decoherence in quantum processors. Specifically, the accidental multi-photon resonances can promote the transmon by multiple levels, affecting the fidelity of quantum computations1. This understanding is crucial for the development of robust quantum computing architectures, particularly in the context of quantum cryptography and simulation. So what matters to practitioners is that these findings highlight the need for careful calibration and control of measurement drive amplitudes to mitigate errors and maintain quantum coherence.