Why Cloud Migrations Fail (and How to Avoid It)

Cloud migrations are rarely derailed by the cloud platform itself. AWS, Azure, and GCP are all mature enough to run almost any enterprise workload reliably. What derails migrations is nearly always one of three planning failures.

Migrating everything at once

Treating a migration as a single cutover event — rather than a sequence of workload-by-workload moves — concentrates risk into one high-stakes weekend instead of spreading it across many low-stakes ones. When something breaks in a big-bang migration, it's hard to isolate which of forty simultaneous changes caused it.

The fix is unglamorous: inventory workloads, rank them by dependency and risk, and migrate in waves small enough that a failed wave can be rolled back without taking down anything else.

Assuming cost parity with on-premises

Lift-and-shift migrations frequently cost more in the cloud than the on-premises footprint they replaced, because on-premises capacity was sized for peak load year-round, while cloud billing is metered continuously. Without rightsizing, reserved capacity planning, and a cost allocation model before migration, the first bill is often the first unpleasant surprise of the project.

No clear owner for the landing zone

A "landing zone" — the account structure, networking, and security guardrails workloads land into — needs to exist and be owned before the first workload moves, not designed reactively as issues come up. Migrations that skip this step end up with inconsistent security postures across teams that migrated independently, which is expensive to unify later.

None of these are hard problems to solve. They're just easy to skip when the pressure is to show migration progress quickly. The migrations that go smoothly are the ones where landing zone design and workload sequencing happened before any workload moved — not during the first outage.