A probation period exists to force a decision on a date you picked in advance. That is the whole mechanism. It does not give you legal permissions you did not already have, it does not make a firing safer, and it does not improve anyone's performance on its own. What it does, when it is built properly, is put a date on the calendar before the new hire starts, and hang enough written detail off that date that the answer is obvious when you get there.
Most probation periods fail quietly. Nobody misses the date on purpose. The first weeks are busy, the check-in gets moved twice, and then it is week eleven and the only record of anything is a Slack thread. If that is where you are, you have not ruined it. You have lost some evidence and some goodwill, and both can be partly recovered. But it is worth understanding what you were supposed to be buying.
The thing you are actually buying is a deadline
In nearly every state, employment is at will absent a contract or a union agreement, which means the probation period is not what gives you the ability to end the relationship. That was already true on day one and it is still true on day 400. The Department of Labor oversees the federal wage and hour rules that apply across all of it, and none of those rules change because you called the first ninety days probationary.
So the value is organizational, not legal. A defined period does three useful things. It tells the new hire that judgment is being formed now and will be delivered on a specific date, which is far kinder than open-ended silence. It gives the manager permission to say something at week three instead of waiting for an annual review. And it creates a forcing function on you: someone has to sit down before that date and write an answer.
People who have run a lot of these stop thinking of probation as a trial and start thinking of it as a scheduled conversation with prerequisites. The date is not the event. The preparation is.
What separates a good one from a barely adequate one
A barely adequate probation period is a sentence in the offer letter and a number of days. It ends by expiry. Nobody signals anything, the date passes, and the employee is now permanent by default, which means you have converted a decision into an accident.
A good one has five parts, and all five are set before the start date.
- A written standard for this role. Not values, not attitude. Three to six things that will be visibly true if the hire is working: the accounts they own outright, the tasks they no longer need checked, the volume they handle unassisted. Write them in a form where a reasonable outsider could tell whether they happened.
- One named person who owns the decision. If two managers are both sort of responsible, neither will prepare and both will defer.
- Check-ins already on the calendar. Week two, week six, and then the decision meeting. Booked before the hire's first morning, with the decision meeting a week before the period actually ends so there is room to act.
- A short written note after each check-in. Four or five lines, sent to the employee. What is going well, what needs to change, what happens next. This is the difference between feedback and a feeling.
- A stated consequence. The employee should know, in plain words, what the end of the period means: confirmation, an extension with specific conditions, or an end date.
The gap between those two versions is maybe two hours of setup work spread over three months. It is the cheapest process improvement available in hiring, which is exactly why it gets skipped.
You are week eleven with nothing written. Here is the recovery
Do not backdate anything or write a retrospective file of complaints. That is worse than having no records, and anyone reviewing it later will see what it is.
Instead, do this in order. Write down, today, what you actually believe about this person and what evidence you have for it. Separate the two columns honestly. You will usually find one of three situations: you know this is working, you know it is not, or you genuinely cannot tell because nobody has given the person a clear target.
If you know it is working, confirm them and say so in writing this week. Do not let the date drift into ambiguity when you already have your answer.
If you cannot tell, extend once, in writing, with a specific and short list. Say plainly that the first stretch was light on direction and that you are fixing that. Name the three things you will be looking at, the date you will look, and who is meeting with them weekly until then. Employees almost always take this well, because it is the first time anyone has told them what the job is.
If you know it is not working, act on the original date rather than the extended one. An extension you do not believe in is a favor to you, not to them, and it costs them weeks they could spend job hunting.
Two wording details worth fixing before the next hire
First, do not let the paperwork imply that surviving probation converts someone to permanent or for-cause employment. Language like "upon successful completion you will become a permanent employee" is exactly the phrasing that creates an expectation you did not intend. State that employment remains at will before, during, and after the period, and have an employment attorney read the standard letter once. It is a small fee against a policy you will reuse for years.
Second, decouple the probation period from benefits eligibility, or at least know how they interact. If health coverage begins on the first of the month after sixty days and your review sits at ninety, you have a hire who has already enrolled and a decision that now carries a different weight. Neither arrangement is wrong. Knowing which one you have prevents an awkward surprise in week thirteen.
The managers who get good at this are not better judges of people. They just refuse to let the date arrive unprepared, and they treat the first written standard as something the new hire is owed rather than something the company holds over them. Set the next one up in an afternoon and you will spend the following ninety days managing rather than wondering.