Measuring probation and onboarding: why a hire is only a success after 90 days

Most recruiting metrics end at the contract signature. Time-to-hire, accept rate, cost per hire - all measure the path to the yes. But the yes isn't the outcome. The real outcome only shows afterwards: does the person stay? Do they become productive? Do they pass probation and become a real gain for the team after 90 days? A recruiting function that only measures the path to the signature judges itself too early.

The most expensive recruiting mistake is the fast mis-hire: someone hired in four weeks who leaves again after eight. From the time-to-hire view that was a success - from the company's view it was a double process, double onboarding and a hole in the team. That's exactly why the post-hire phase belongs in your measurement, otherwise you optimise for speed at the cost of quality.

Early attrition measures how many new hires leave the company again within the first months - often measured by the first 90 or 180 days. It's the most unsparing metric for the quality of your hires, because it can't be glossed over: whoever leaves early was either a mis-hire or had an onboarding that lost them. Both are signals you want to see.

It's important to break down early attrition: was it the selection (expectations didn't match reality) or the onboarding (the person felt lost)? The answer leads to different measures. High early attrition for selection reasons sends you back to the requirements profile and the interview; one for onboarding reasons sends you into the first 90 days. The bare number isn't enough - you need the reason.

The probation pass rate is the positive sister of early attrition: how many of your hires get cleanly through probation and become a permanent part of the team? A high rate means your selection and onboarding fit together. A low rate is an early warning signal, long before it shows in employee satisfaction or attrition.

Harder but more valuable is quality of hire - the attempt to measure the actual quality of a hire. There's no perfect number for it, but usable approximations: the manager's assessment after 90 days, the achievement of first goals, whether a person from the same source and with a similar profile was a good or poor hire. Quality of hire is the bridge between recruiting and business outcome - and exactly therefore the metric that enables the most learning.

The real value of these metrics only emerges through the feedback loop. If after 90 days you know which hire was good and which poor, you can feed this insight back to the start of the process. Was the good hire from a certain source? Did they have a profile your requirements profile didn't describe at all? Did the poor hires fail on a criterion the interview never tested?

This feedback closes the loop. Recruiting without 90-day feedback is an open funnel: you put in effort and never see whether what came out the bottom was really good. With feedback, recruiting becomes a learning system - every hire makes the next requirements profile, the next interview and the next source choice a bit better.

These metrics almost always fail because the data breaks after the hire: the ATS ends at the signature, the HR system begins afterwards, and nobody connects the 90-day outcome back to the application, the source and the interview rating. Without this connection you can't learn which source and which rating predicted good hires.

KI BMS helps by keeping the application from disappearing at the hire - it stays in the archive with source, scorecard and audit log. That way you can mentally tie the later 90-day outcome back to what was visible in the application process - and check whether your interview ratings and source choice really predicted the good hires. The actual probation management belongs in the HR suite, but the recruiting side of the feedback - what did we see in this person and was it right - stays traceable.