For this reason, if the number of users and merchants in the network exceeds a certain scale -- "a critical mass" -- the scale of the payment platform would expand greatly, leading to an oligopoly or monopoly in the retail payments market.
If specific businesses gain strong control over the retail payments market, it could distort the pricing mechanism, decrease incentives for innovation, or increase systemic risk when problems arise. At present, the Japanese retail payments market is not facing any oligopoly or monopoly.