This article argues that modern Financial Services (FS) data platforms must deliberately support two distinct but complementary promotion lifecycles. The well known and understood North/South lifecycle provides operational stability, governance, and regulatory safety for customer-facing and auditor-visible systems. In parallel, the East/West lifecycle enables analytical exploration, experimentation, and rapid innovation for data science and analytics teams. By mapping these lifecycles onto layered data architectures (Bronze to Platinum) and introducing clear promotion gates, FS organisations can protect operational integrity while sustaining analytical freedom and innovation.