Do humidifiers with a humidistat or auto mode actually work?

Evaporative and smart models with built-in humidity sensors earned the most praise across r/BuyItForLife and r/Humidifiers for shutting off automatically and avoiding wet surfaces. However, multiple reviewers — especially of certain mist-free 'invisible' models — reported that the on-device humidity reading frequently failed to reach the target setting, so accuracy varies by model.