What are cheap shots exactly

Comparing spar to the real art of the sword we now call fencing ,cheapshots simply do not exist.

Its all about looking for your opponents weakness and striking there making sure you will be well deffended when your opponent strikes back and keeping a good distance from your enemy.
I usualy use a saber so I am unfamiliar with some epei and foil technique but I know that if I was on epei and kept stabbing your arm every time you let it be vulnerable it would be kinda cheap but it is completely your fault for letting it be vulnerable and not protecting yourself.

Spar uses a saberlike sword so cheapness is not a thing , if you are repeating the same moves over again your opponent should not fail to that, they should be able to use a new stradegy and rek u.

How exactly would any hit be cheap and trashy if I am not lagging or delaying alot.