FrogReaver
The most respectful and polite poster ever
It's not the same outcome, because with success you're in combat with somebody prone. With failure you're in combat with somebody standing. And if you hadn't tried you wouldn't be in combat.
Now, I suppose it could be argued that both outcomes are worse than doing nothing at all, but presumably this wouldn't have happened unless that player had decided this wasn't true.
And, really, this is (also) a semantic game, because knocking somebody prone uses an attack action, so what really happened here is the DM gave the PC a surprise round. If he failed with his shove it's still a wasted turn.
When you start seeing everything as a semantic game then you've lost some perspective.
Anyways, the point your making is that IF combat ensues due to the prone attempt then being in combat with a standing opponent is different than not being in combat with a standing opponent.
I can't argue there. Now consider the same example where combat doesn't ensue due to your attempt to knock the opponent down. What is the meaningful consequence of failure in that case?