5 Critical Mistakes to Avoid in Cloud Migration

Cloud migration projects fail more often than they succeed. According to McKinsey, organizations capture only about 10% of the value they expected from cloud transformations. The mistakes that doom these projects are predictable — and avoidable, if you know what to watch for.

Mistake #1: Lift-and-Shift Without a Strategy

The most common approach to cloud migration is "lift-and-shift" — moving applications to the cloud exactly as they are. While this seems like the fastest path, it often results in higher costs and missed opportunities.

When you move an application designed for on-premises servers to cloud infrastructure, you're essentially renting someone else's hardware. You don't benefit from cloud-native capabilities like auto-scaling, managed services, or serverless computing. Worse, you often pay more for the same performance because cloud pricing models assume elastic usage patterns.

Better approach: Categorize applications by strategic importance and technical debt. For commodity applications that are being retired soon, lift-and-shift is fine. For strategic applications that will live in the cloud for years, invest in re-architecting to leverage cloud-native capabilities. The upfront investment pays back quickly through lower operating costs and better scalability.

Mistake #2: Ignoring Total Cost of Ownership

Organizations frequently focus on infrastructure costs while ignoring the full picture. Cloud costs include compute, storage, and networking — but also data transfer fees (especially egress), licensing costs for databases and operating systems, managed service fees, support contracts, and the cost of migration itself.

We've seen organizations shocked when their first real cloud bill arrives 3x higher than projected because they didn't account for data transfer costs between regions, or because cloud provider database licensing works differently than what they were used to on-premises.

Better approach: Build detailed cost models before migrating. Use cloud provider pricing calculators, but validate with actual usage patterns from your monitoring systems. Plan for cost optimization (FinOps) as an ongoing practice, not a one-time activity. Reserve instances and savings plans can reduce costs by 30-60%, but only if you plan for them.

Mistake #3: Security as an Afterthought

The shared responsibility model means cloud security works fundamentally differently than on-premises security. The provider secures the infrastructure; you secure everything you put on it. This distinction trips up even experienced teams.

Common security gaps that appear during and after migration:

• Overly permissive IAM policies that grant broader access than needed
• Storage buckets or databases accidentally exposed to the public internet
• Unencrypted data at rest and in transit
• Inadequate logging and monitoring that leaves blind spots
• Missing network segmentation that allows lateral movement

Better approach: Design security into your cloud architecture from day one. Implement a secure landing zone before migrating any workloads. Use infrastructure as code to enforce security controls consistently and repeatably. A dedicated Cloud & DevOps team that owns the infrastructure foundation prevents these gaps from forming in the first place.

Mistake #4: Underestimating Application Dependencies

Applications rarely exist in isolation. They connect to databases, call APIs, integrate with other systems, and depend on specific network configurations. Organizations that don't fully map these dependencies face painful surprises during migration.

A common scenario: a team plans to migrate a customer-facing application over a weekend. Mid-migration, they discover it depends on a legacy system that can't be accessed from the cloud network. What was supposed to be a weekend cutover becomes a multi-month project to establish secure connectivity and rearchitect the integration layer.

Better approach: Conduct thorough discovery before planning migration waves. Use application dependency mapping tools and validate findings with application owners. Plan migrations in groups of related applications that can move together, reducing the need for complex hybrid connectivity.

Mistake #5: Not Planning for Day-2 Operations

Migration is not the finish line — it's the starting point. Organizations often focus so heavily on the migration itself that they don't prepare for operating in the cloud long-term.

Post-migration operational challenges include:

• Teams lacking cloud-specific skills for troubleshooting and optimization
• Monitoring tools that don't work well in cloud environments
• Incident response processes that assume on-premises access and don't account for cloud provider APIs
• Cost management without governance — cloud spending spirals without controls
• No automation for routine operations, leading to manual toil

Better approach: Build cloud operations capabilities in parallel with migration. Train teams, implement cloud-native monitoring, and establish FinOps practices before the migration completes. Consider dedicated Cloud & DevOps pods that own operational excellence as a continuous practice, not a project with an end date.

The Common Thread: Continuity Matters

Across all five mistakes, there's a pattern: cloud migration fails when it's treated as a one-time event rather than an ongoing capability. The organizations that succeed build dedicated teams with cloud expertise, give them ownership of the migration and the resulting cloud environment, and maintain that continuity through operational maturity.

Cloud done right delivers real value — agility, scalability, resilience, and often meaningful cost savings. But it requires the kind of sustained, disciplined execution that only comes from stable teams with deep context and clear ownership.