is it time to put my employee on a formal improvement plan?

This post was written by Alison Green and published on Ask a Manager .
A reader writes:
I inherited an employee who was never held accountable by his previous manager (for example, he completed a major web software overhaul nine months past the deadline with no consequences). As a result, I’ve been vigilant about giving him feedback every time he doesn’t do something he says he’s going to do by when he says he’s going to do it. I’ll often see improvement after these conversations, only to see this habit creep back up again after a few months. It’s usually something small — like saying he’ll send me a preview of the newsletter or update me on a project and then not getting to it or explaining why he didn’t. All of these little things add up to someone who I can’t count on for major long-term projects.
So, is it time for a formal performance improvement plan (PIP)? Are you supposed to warn someone before putting them on a PIP? Is that the right next move, or is there something else I could try?
I answer this question — and three others — over at Inc. today, where I’m revisiting letters that have been buried in the archives here from years ago (and sometimes updating/expanding my answers to them). You can read it here .
Other questions I’m answering there today include:

Emergency bathroom use during interviews
How can I end our birthday lunch tradition?
The details in my offer letter aren’t what we discussed

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