Common mistakes with serverless architecture in B2B marketing often involve over-engineering simple tasks, leading to unnecessary complexity for straightforward marketing automations. A significant oversight is inadequate cost optimization, as event-driven billing can quickly escalate without proper monitoring and control for high-volume campaign triggers or data processing. Many businesses also struggle with complex debugging and monitoring across distributed functions, making it difficult to pinpoint issues or track user journeys effectively in a multi-stage marketing pipeline. Furthermore, there's a risk of vendor lock-in if proprietary services are heavily utilized, hindering future flexibility or migration strategies. Neglecting data security and governance for sensitive B2B customer information processed by ephemeral functions can lead to serious compliance issues and erode trust. Finally, firms often fail to design for seamless integration with existing MarTech stacks, creating data silos instead of a unified customer view.