An underperforming employee is a situation with a clock on it whether or not anybody starts one. The cost of waiting is not neutral: the work still has to be done by somebody, the team notices long before the manager acts, and every week of silence makes the eventual conversation more of a surprise and therefore more contested. This page is about the first four weeks after somebody notices, written for the manager and the HR owner who will both be in the room.
Week one is for establishing what is actually true
Check whether the expectation was ever stated, whether it is being measured the same way for everybody in the role, and whether something changed in the work. A surprising share of underperformance turns out to be an expectation that moved without being restated, and that is a different problem with a different and much cheaper fix.
Week two is the conversation nobody wants
Specific, recent, and about the work rather than about the person. The test of whether it landed is simple: ask them to say back what needs to change. If what comes back is vague, the message was vague, and repeating it in writing afterwards is what turns a chat into a record both sides can rely on.
Weeks three and four are for support and a clock
Name the support you are actually providing, put a date on when the change should be visible, and say what happens if it is not. Ambiguity here is kindness that costs both sides: the person cannot prioritize what they do not know is at stake, and the employer cannot rely on a warning that was never given.
What has to be written down
The date, what was said, what was agreed, what support was offered and when it will be reviewed. Not for a file, for the next conversation, which will otherwise start with two different memories of this one. Kept against the person and the role, it is also what lets a new manager pick the situation up without starting again.
Questions people ask about underperforming employee
How long should you wait before acting?
Long enough to be sure it is a pattern rather than a bad fortnight, which for most roles is a few weeks. Waiting a quarter to be certain usually costs more than being wrong would have.
Should HR be in the first conversation?
Usually not. The first conversation is the manager's and is about the work. HR belongs in the process, the consistency between managers and the record, and arrives formally if the situation does not improve.
What if the underperformance is a health or personal matter?
Then it stops being a performance process and becomes a different one with its own obligations. That is the point to involve HR and your own employment counsel rather than to continue on a performance track.