A(Li) measurements of NGC 6633 giant stars as a function of T_eff compared to stellar evolutionary tracks (Lagarde et al. 2012) with and without rotational effects for solar metallicity (Z = 0.014) and relevant masses. The beginning of different evolutionary stages are marked with descriptions. The coloured symbols represent LTE A(Li) measurements for the giant stars of NGC 6633 from Morel et al. (2014), Magrini et al. (2021), Tsantaki et al. (2023) with 3D NLTE corrections from Wang et al. (2021), while the grey symbols mark the same measurements, but with NLTE corrections from Lind et al. (2009). The observations should be matched by the thick horizontal parts of the tracks, and the apparent match between models and observations for the green and red tracks is not real, as it assumes all giants belong to the fast-lived RGB phase.