I hope the intention was clear: with 400 million users, it is a certainty that a feature will be incomprehensible, unusable, etc., to some non-zero number of users.
I'm now wondering what the rigorous way to describe the phenomenon you describe is. Something like, as the number of realizations of a random variable increases, the probability of seeing a realization below a given threshold approaches one. This sounds a lot like some of the theory related to hypothesis testing but it's been too long.
I'm now wondering what the rigorous way to describe the phenomenon you describe is. Something like, as the number of realizations of a random variable increases, the probability of seeing a realization below a given threshold approaches one. This sounds a lot like some of the theory related to hypothesis testing but it's been too long.