Bar corotation radius vs. bar length for Auriga galaxies. Top panel: corotation radius as a function of bar length for the barred Auriga galaxies, denoted by the symbols in the figure legend. The colour-coding corresponds to measurements at different redshifts, while for the galaxies for which we use the TW method (Au-TW) we estimate the pattern speed at z = 0. These are compared to data from Corsini (2011) and Aguerri et al. (2015) (grey points); the error bars indicate the 1σ uncertainties. The lower and upper dashed grey lines indicate ℛ = 1 and ℛ = 1.4, respectively. Bars in Auriga are fast across all redshifts. Bottom panel: mean ℛ for the aforementioned observations for barred galaxies in Auriga and for the EAGLE and Illustris barred galaxies from Algorry et al. (2017) and Peschken & Łokas (2019) at z = 0. The error bars indicate the 2σ error on the mean. The dashed line indicates ℛ = 1.4, below which bars are considered fast. Bars in the Auriga simulations are fast, compatible with observations, while bars in EAGLE and Illustris are excessively slow at z = 0.