Nature Reviews Physics, Published online: 16 July 2026; doi:10.1038/s42254-026-00960-7 Various observed behaviours of overdoped cuprates are inconsistent with a weak-coupling, Fermi-liquid-based Bardeen–Cooper–Schrieffer description. This Perspective argues that these behaviours are consequences of substitutional disorder in a d-wave superconductor with a short-correlation length, and that a weak-coupling approach is possible in the disorder-free limit.