Launching mechanisms. Panel a: parameter space for thermal winds. The green solid lines show the different wind regions boundaries described in Begelman et al. (1983). In regions A and B (in shaded green), thermal winds can be launched, while this mechanism is suppressed in regions C, D, and E. Panel b: Magnetic versus radiative driving. The dashed purple line shows the possible threshold separating radiatively driven (λ_Edd ≳ 0.1) winds from MHD winds, described in Sądowski & Gaspari (2017). The dotted orange line present the threshold between the two mechanisms on the basis of the outflow velocity. The shaded regions show the intersection between the two conditions. Particularly, winds in the purple shaded region are likely to be radiatively driven, while those in the orange shaded regions are possibly MHD driven. The S23 UFO sub-sample is shown in red circles, T10 in blue diamonds, and C21 in black squares.