it depends from which perspective you look at it. let's say developer, the developer wants to make profit so if he reaches a profit it could be a success as long as it wasn't much below expectations which could mean he will make other games in the future which he expects higher profit from.
as gamer, let's say someone who wants to play online with a "healthy" online community, the games has to sell a decent amount because otherwise the online community will die fast and you won't find enough online games anymore or the developer will shut down the servers if there aren't enough people even if you want to play it online for years.







