According to the PMBOK guide, a hybrid approach is a combination of predictive and adaptive (agile) methodologies that suits the project context and stakeholder needs1. A retrospective is a meeting held at the end of each iteration in agile projects, where the team reflects on what went well and what can be improved2. The PMI-PBA guide also states that retrospectives are a valuable tool for business analysts to identify and address issues, risks, and opportunities for improvement3. Therefore, the best way for the project manager to deal with the decline in productivity is to discuss the issue in the next retrospective with the team and collaboratively find solutions to enhance their performance. References:
* 1: PMBOK guide, page 19
* 2: PMBOK guide, page 207
* 3: PMI-PBA guide, page 129