Earlier quoted context omitted.
> Stripe has all the power to prevent many forms of fraud and provides this as a service as long as you pay a premium for it in the form of Radar. You have to pay extra on top of the 2.9% + 30c per transaction to get this protection. Radar's ML-based shield is free for all accounts on standard pricing. See https://stripe.com/pricing#radar-pricing . (We only charge if you want to set custom rules etc.)
> (We only charge if you want to set custom rules etc.) The rules are what really allows merchants to protect themselves against fraud but this information isn't possible to obtain without help from their payment gateway (ie. Stripe). In other words, merchants have no reasonable options to set up rules like what Radar does while using our own custom logic because there's no API that Stripe provides for us to get thin…
If you don't choose to write your own software using your own data, that's cool; you can buy that software from us, for two cents a transaction (or less).
We're a software company selling to software developers. We're cool with you writing your own software with your own data if you think your engineers are sufficiently efficient at this to make that the best possible use of their time. (The businessman in me suggests that it is extremely unlikely you can profitably employ engineers to write this software at most likely scales of your business and, contingent on being able to do that, it is quite likely there are a hundred better projects not upper bounded at 2 cents a transaction, but you are a project away from constructively disproving this if you strongly disagree.)