OPS.10.1:8 - Common Anti-Patterns and How to Avoid Them

Tempting move	Consequence	Repair
Replace the utilization factor by the busy fraction alone.	The rise in waiting near saturation disappears from the mean calculation.	Retain `rho/(1-rho)` with the selected model’s premises.
Put mean durations into one schedule and report its deadline as assured.	Different uncertain paths collapse into an unrepresentative outcome.	Calculate the required predicate over the joint paths or derive an applicable bound.
Deduct interruption time after already including it in effective service.	The same capacity loss is counted twice.	Choose a consistent service/availability representation.
Apply the old one-server model after pooling resources or changing service dependence.	The mathematical account no longer describes the proposal.	Reconstruct the affected service mechanism before comparing its result.