In 2021 we ran a small fintech in Kyiv. Onboarding leaked: roughly 1 in 10 OTPs never arrived, and our SMS provider would shrug and say "carrier issue." We were paying for invisible failures while users churned.
The B2B providers we tested wanted yearly commits and quoted us in calls, not on a page. The cheap providers had a TG bot UX, no docs, and zero refunds.
So we built the thing in the middle: honest pricing on a page, an API a developer can ship in 10 minutes, and a real refund when no SMS arrives. Two engineers, one weekend prototype, three months to first paid team.
Four years later we're 28 people, still bootstrapped, still refunding every undelivered SMS automatically. We don't have an enterprise sales team — we have docs.