A Kaizen event should never be an excuse for a layoff. Make no mistake, productivity improvements are expected. If a process improvement is accompanies shortly thereafter by a layoff, this will be the kiss of death for any enthusiastic future involvement by the workforce.
Make no mistake, we do expect to achieve productivity improvements through our Kaizen efforts. Workers who are now excess in a particular area should be reassigned to another area, or assigned to work on TPM and process improvement projects. Remember that we need to have some percentage of the workforce available to work on improvements; otherwise progress will be very slow.
If excess workers cannot be reasonably absorbed in this fashion, a reduction in headcount should take place through normal attrition (normal turnover). This may take longer to accomplish, but it is well worth the additional cost to the company in the future.