Makes sense. Probably how one would approach it during a system design interview.

> How many times do you buy things during a day? Once? twice? Maybe thrice?

None most days. But then some days eight or nine subscriptions go through. Guess it averages out.

Might be spiky though, around the beginning and ends of each month. If paying out wages monthly, and at the end of the month or beginning of the next one is prevalent across countries where a significant share of the population has both access to a bank account and sufficient enough income to regularly spend either by card or online.

Did this turn into a systems design interview?

Anyway, joking aside, I was mostly amused by what my frame of reference for throughput / service load has become.