Use a subscription billing platform for the recurring-charge process when the enterprise accounting system and its available billing modules cannot handle the business’s pricing, amendments, or customer interactions reliably without excessive manual work. The strongest reasons are concrete: usage charges that require spreadsheet calculation, frequent plan changes that need custom adjustments, or self-service upgrades that cannot reach the billing record safely.
This usually means giving a dedicated billing engine responsibility for subscriptions while enterprise accounting continues to manage the financial books. It is not a reason to discard the ledger or financial controls. Some enterprise suites already include capable subscription modules, so the decision should compare the configured suite, a suitable module, and a separate platform against the same real business scenarios.