The normal-state properties of cuprate superconductors are determined by the competition involving the superexchange energy between antiferromagnetically-correlated Cu moments and the kinetic energy of dopant-induced O 2p holes. At high temperature, we get an incoherent bad metal. On cooling, coherence in both charge dynamics and spin correlations appears with the development of intertwined dynamic correlations. In reciprocal space, coherent quasiparticles develop in the near-nodal region while spin correlations limit coherence in the antinodal region. With overdoping, kinetic energy wins out and superconducting order disappears with the loss of antiferromagnetic correlations. Dopant disorder and the lack of long-range Coulomb screening result in a distribution of local environments with varying hole concentration, which complicates comparison between different probes and with theory. The strongest superconductivity develops where the normal state is inconsistent with expectations for a Fermi liquid, thus creating a challenge for understanding the superconducting mechanism.