Feeds and speeds, materials and choice of bits.
Then there's RPM on the bit, how many cutting edges and the material the bit is made out of. The cheaper bits (often steel body with carbide cutting edges) are not generally intended to be machine driven (relentless and constant motions). I've found on the smaller bits (3 mm cut), the cutter shank can bend and then the cut width is more like 3.something_bigger). The machine rigidity also plays an important role WRT vibration - often causing bit wear/breakage and trashed parts. Clamping of material is very important too.
A good helper is a directed compressed air stream at the bit into the cut path. This helps keep the bit cool and avoids re-cutting the chips - extending tool life and providing a better finish.
Quite a bit of trial
xender discord omegle and error to find the "sweet spots" for your machine but a good trap is to cut too slowly at too low an RPM for fear of breaking bits. Also being a "hog" can break bits quickly too. Again a bit of practice like you did with the hand tools.
If you find test files in the wild watch out for speeds, feeds, rapids and measurement systems (inch, metric) and that the drawings fit within your machine boundaries.
A full depth cut might only be practical on a finishing pass, too shallow and the tip wears quickly.
Sorry, not much to say about what might work or not for your machine - it depends.
Like welding, the "right" sounds are learned as the quality improves (and the bits don't break :-).
Have fun but stay safe! :-)