If you're into photography as I am you'll know about the term over-etched. It happens a lot in Photoshop or Lightroom where there's a tempting control called Sharpness.
Because in photography focus is a function of the camera lens, once you get your picture, the focus is however you shot it. Unchangeable. You cannot get it more in focus.
But then, there's that sharpness control.
The sharpness control doesn't actually affect the focus. Instead, it adds contrast between the transitions in the image. Thus, the image appears sharper.
Too much of this control and the image becomes over-etched. Unnatural. The contrast between edges is forced and overcooked.
In audio, we have the same sort of problem. When a system is somewhat dull, a bit lifeless, muddled, we can try and remedy the problem by increasing the high frequency balance—adjusting the tweeter or switching to brighter cables. This can help those transitional edges.
Of course, as in photography, it is better to not have the problem in the first place: better focus, less midrange muddle.
There's nothing wrong with small adjustments.
Just be careful not to overdo it.