Comeback Mechanic

A comeback mechanic is a mechanic that is meant to help the losing person. It is meant to help him or her make a comeback in a fighting or racing game.

Done Right
When done right, comeback mechanics help level the playing field and help close the skill gap. Examples of games that do them right include Mario Kart 8, Super Smash Bros. Ultimate, and Crash Team Racing.

Done Poorly
While doing comeback mechanics right can level the playing field, doing them poorly can straight up ruin a game by allowing the less experienced players to get a cheap win. Mario Kart Wii goes WAY too far with this. The item balance and atrocious rubberbanding of this game can cause way too much chaos. Too often, you won't get a chance to separate yourself from other racers before the next item hits, which is really annoying. The new items are the worst offenders to the item balance. These items are the POW Block, which is just a weaker Lightning; the Mega Mushroom, which is a weaker Star; and the Thunder Cloud, which shrinks you unless you pass it off to another player.

What Happens If Comeback Mechanics Aren't In The Game?
If comeback mechanics don't exist in a game, the less experienced players won't be able to make a comeback, and that makes the game boring since more experienced players have a higher chance of winning this way.