Triming Hole into surface

Since I was having issue with the Make hole function on a planar surface. I had the Idea of using the Trim Function.
Placed a cercle on a planar surface then use the Trim.
It works if and only if one Isocurve cuts the curve… I guess the issue is that when you click and no isocurve are nearby, the routine does not seem to know what you are selecting and never trims.

Is there a trick other than increasing the isocurve density until at least one is cutting through your triming curve?

Use a display mode that shows surfaces such as Shaded or Ghosted to pick the trim areas. You don’t need isocurves in that case.