Extrapolation of current project performance into the future is inherently unreliable.
Projects evolve through distinct phases, each with its own risks, constraints, and execution conditions. There is no basis to assume that:

• Occurred risks will occur again
• Avoided risks will continue to be avoided
• Project Risks are consistent across all stages of delivery
• The drivers of past performance will remain unchanged
• All activities contribute equally to overall performance

These assumptions oversimplify project delivery complexity.

In practice, EVMS tends to explain and justify delays and cost overruns after they happen, rather than enabling teams to proactively prevent them.

It is valid to identify systemic risks (those with end-to-end impact) and use them to inform forward-looking insights. However, the EVMS methodology oversimplifies project complexity, leading to the assumption that most performance variances are systemic. In reality, many variances do not have a uniform impact on overall project outcomes.

Extrapolation based on aggregated performance metrics can distort the true picture and lead to misguided decisions.