For years, players in Valve’s competitive MOBA, Dota 2, have noticed a curious trend: Matchmaking Rating (MMR) numbers seem to climb steadily upwards across the player base. What once signified a truly elite player, a certain MMR threshold, now appears to be a more common achievement. This isn`t just a perception; it`s a systemic phenomenon known as MMR inflation, a concept recently dissected by prominent Dota 2 analyst and commentator, Maelstorm.
The Economic Paradox of Digital Rating
Imagine MMR not just as a numerical representation of skill, but as a digital currency within the Dota 2 economy. In a perfectly balanced system, this currency would be exchanged between players: when one player gains MMR, another loses an equal amount. The total sum of MMR in the system would remain constant, or at least stable. However, Maelstorm`s analysis suggests that Dota 2’s MMR system has a critical flaw, a built-in mechanism that continuously injects new “currency” into the system without an equivalent mechanism for removal.
The core of the issue, according to Maelstorm, lies in the system’s inability to allow a player`s rating to fall below a certain floor, specifically 1 MMR. While the concept of a rating floor might seem like a safety net for new or struggling players, it inadvertently creates a perpetual inflation machine.
The “Zero Lower Bound” Problem Explained
Consider a scenario at the very bottom of the MMR ladder. When players with 1 MMR participate in a match, the system operates under a seemingly logical principle: winners gain points, and losers lose points. However, if a player with 1 MMR loses a game, their rating cannot drop below 1. They don`t lose the expected 20 or 30 points; they simply stay at 1.
Now, let’s apply this to a simple match: a team of five 1 MMR players plays against another team of five 1 MMR players. If one team wins, its players gain, say, 20 MMR each, totaling 100 MMR gained for the winning team. The losing team, already at 1 MMR, cannot lose any points. They effectively lose 0 points from their displayed rating. The net effect? A new 100 MMR “currency” has been created and injected into the system, not balanced by an equivalent loss.
This process, repeated across countless matches involving players at or near the lowest possible MMR, continuously adds points to the global pool. These newly generated points don`t just accumulate at the bottom; they flow upwards through the system, disproportionately benefiting players with win rates consistently above 50%. As they climb, they effectively absorb this newly minted MMR, pushing their own numbers higher without necessarily undergoing a significant increase in raw skill relative to the rest of the player base.
The Double Down Dilemma: Adding Fuel to the Fire
As if the foundational design wasn`t enough, the introduction of Double Down tokens has only exacerbated the problem. These tokens allow players to double their potential MMR gains (or losses) for a single match. Maelstorm points out that while the intention might have been a symmetrical risk/reward system, the underlying “zero lower bound” principle still applies.
If a player uses a Double Down token and wins, they gain 40 MMR. If they use it and lose, and they are at 1 MMR, they still only lose 0. The double gain is real, but the double loss, at the bottom, is not. This effectively allows an even faster injection of new MMR into the system, acting as an accelerant to the existing inflationary trend.
Consequences and the Call for a Reset
The most significant consequence of MMR inflation is the gradual erosion of what a specific MMR number truly signifies. When everyone`s numbers are creeping up, achieving a higher MMR might feel like progress, but if the entire scale is shifting, the relative skill level might remain unchanged. This can lead to skill discrepancies within what appear to be the same medal ranks, making competitive integrity harder to maintain.
Valve`s last major overhaul of the MMR system was in November 2017, introducing the medal system and bi-annual recalibration. However, as Maelstorm notes, the fundamental mechanics of point distribution have remained largely untouched since then. The periodic recalibration serves more as a soft reset, shuffling players around within the inflated pool rather than purging the excess MMR from the system.
This sentiment resonates with professional players as well. Vladimir “No[o]ne” Minenko, a well-known Dota 2 pro, has independently voiced concerns about MMR inflation, aligning with Maelstorm`s theory and advocating for a periodic, perhaps more stringent, MMR reset for all players. Such a reset, akin to seasonal ladder resets in other competitive games, would effectively “reboot” the MMR economy, clearing out accumulated inflation and re-establishing a more accurate skill distribution.
The Path Forward
While the current MMR system provides a sense of continuous progression, the reality of inflation suggests that this progression may be more illusory than real. For Valve, the challenge lies in deciding whether to address this inflation directly—perhaps through a hard reset, a dynamic decay system, or a fundamental re-evaluation of how MMR is lost at the lowest tiers—or to let the numbers continue their unstoppable ascent. The question isn`t if the MMR will keep rising, but what it will mean when it does.
Finley Holt