 One can characterize violations of naturalness as instances of fine-tuning in that, where naturalness is violated, low-energy phenomena depend sensitively on the details of some unknown fundamental theory concerning phenomena at very high energies. Physicists have developed ways of quantifying fine-tuning in this sense (Barbieri &amp; Guidice 1988), critically discussed by Grinbaum (2012). It is controversial whether, to the degree that violations of naturalness can be seen as instances of fine-tuning, they should be regarded as problematic. Wetterich (1984) suggests that any fine-tuning of bare parameters is unproblematic because those parameters depend on the chosen regularization scheme and have no independent physical meaning. As highlighted by Rosaler and Harlander (2019), Wetterich’s perspective depends on an understanding of quantum field theories as defined by entire trajectories \(g^i(\Lambda)\) in parameter space.