Beware the "honeymoon bounce" of a Performance Improvement Plan
Right after you deliver a Performance Improvement Plan, an interesting phenomenon often occurs. For the period of approximately 2-3 weeks after the plan is delivered, the employee who has received the performance improvement plan will appear to improve their performance. I call this the "honeymoon period." During this period, it will seem like the employee is genuinely improving and doing a much better job. It will seem so promising, in fact, that it might appear almost certain that this employee will exit the performance improvement plan successfully. But it is really important to watch out for this. This honeymoon period usually does not last, and the employee often reverts to their prior levels of performance that caused the Performance Improvement Plan to be necessary to begin with.
True improvement in performance can only be measured over a longer period of time. Performance Improvement Plans, therefore, really need to be measured repeatedly over the course of multiple months in order to ensure that that improvement in performance is sustained.