How many QA evaluations do you need per agent per month? Most centers say 5-10. The math says that is not enough.
The Statistical Reality
If an agent handles 1,400 calls per month (70 calls per day, 5 days a week, 4 weeks), and you score 5 of those calls, you are evaluating 0.36% of their work. You are making coaching decisions, performance reviews, and potentially termination decisions based on less than half a percent of what they actually do.
The statistical formula for sample size tells us you need approximately 65 quality monitoring sessions per agent per month to draw reasonably accurate conclusions at a 90% confidence level. Most centers do not come close to that.
Why 5 Calls Is Not Enough
When you score 5 calls, you do not have data. You have anecdotes. One bad call out of 5 makes an agent look like they fail 20% of the time. But if you scored 100 calls and found 4 bad ones, that is a 4% failure rate. The agent is actually performing well. You just got unlucky with your sample.
This is not a theoretical problem. It happens every day in contact centers. Good agents get bad reviews because the sample was too small. Bad agents fly under the radar because the 5 calls that were scored happened to be their good ones.
The AI QA Solution
This is where AI-powered QA changes everything. When you can score every call in under 30 seconds, the sample size problem disappears. You are not sampling anymore. You have the full picture.
OttoQA scores every call with the same consistency. No fatigue. No bias. No cherry-picking. Every agent gets evaluated on their full body of work, not a handful of random calls.
The result is coaching that is based on real patterns, not guesses. Performance reviews that are fair. And data you can actually trust.