  Background: Requirements Changes (RCs) -- the
additions/modifications/deletions of functional/non-functional requirements in
software products -- are challenging for software practitioners to handle.
Handling some changes may significantly impact the emotions of the
practitioners. Objective: We wanted to know the key challenges that make RC
handling difficult, how these impact the emotions of software practitioners,
what influences their RC handling, and how RC handling can be made less
emotionally challenging. Method: We followed a mixed-methods approach. We
conducted two survey studies, with 40 participants and 201 participants
respectively. The presentation of key quantitative data was followed by
descriptive statistical analysis, and the qualitative data was analysed using
Strauss-Corbinian Grounded Theory, and Socio-Technical Grounded Theory analysis
techniques. Findings:We found (1) several key factors that make RC handling an
emotional challenge, (2) varying emotions that practitioners feel when it is
challenging to handle RCs, (3) how stakeholders, including practitioners
themselves, peers, managers and customers, influence the RC handling and how
practitioners feel due to the stakeholder influence, and (4) practices that can
be used to better handle RCs. Conclusion: Some challenges are technical and
some are social which also belong to aspects of agile practice, emotional
intelligence, and cognitive intelligence. Therefore, to better handle RCs with
positive emotions in socio-technical environments, agility, emotional
intelligence, and cognitive intelligence need to cooperate with each other.
