No.. you are CHOOSING to make it actively difficult for the players to retreat. The GAME is not telling you to have these orcs believe "the murderous goons might return to finish the job? Because I want vengeance? Because We're great warriors who will not suffer the insult? Because it's clear we have the advantage because they ran and if they regroup with a larger force, we might lose that"... YOU are doing that. YOU. Not the game. YOU.
This is super weird.
Like, the players don't know whether the people they hit and run will retaliate or thank them kindly for killing Bob because he was a jerk anyway, right?
And I assume that not literally every foe they do this to will adamantly refuse to give chase, right?
And the second something
does give chase the players will see how the game straight up punishes them mechanically for doing so, right?
So they're going to learn not to not retreat at some time or other anyway because they don't actually know when the monster will roll over an snuggle them on the way out, or rain ranged murder into their exposed backs and one result is enough to remove the value of the other.
Because the mechanics suck, this only leaves the option to never play an enemy was anything but uncaring to forgiving toward hit and run tactics instead of actively seeking out better chase mechanics.
This isn't even getting into the anti-heroic feeling of having to break and run from everything because the DM likes a playstyle the game doesn't support. Or the fact that I feel like players aren't going to trust a DM who will absolutely murder them for not retreating won't use the rules to murder them
for retreating. Because the point is operant conditioning.