Not sure that's a feature.. Why would you want to reset your game?

maybe he meant start another character?

Some people waste their money, make bad purchase decisions, accidently sell the wrong item etc, and end up with at a high exp lvl, a low mech level, and no money.
And the recent update has made things worse with the min-vslvl20 for high explvl players.

For example, say someone has vs-lvl=14 (slow at upgrading mech, due to wasting money on kits and such) and exp-lvl=24.
When they get their next level up, (to exp-lvl=25), they will start facing lvl vs-lvl=20 opponents, in battles they can't hope to win, having only a lvl=14 build of mech.
So with no money, and being severely outclassed, they can either keep fighting (and losing) saving up the pittance that you get from a loss, and eventually upgrade their mech to lvl 20 after hundreds of matches of constant losses, they can quit the game for good.

But that's just one possibility (though unlikely/rare).

Like fake already said, you can collect money from constantly loosing in PvP.
But things aren't as bad as they might seem since there's no way to go bankrupt in SM.

If you can't win against other players in PvP, do single player matches. Reward isn't as good as winning in PvP but it is better than loosing in PvP.
Also, you don't have a need to use kits in single player mode. Just battle with NPCs until you loose, then you'll get to face weaker NPC you beat earlier.
Single player mode is also useful for trying out your new weapons/strategies.

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Aeacus