Low-code development platforms promise to empower users to develop business applications without requiring in-depth programming knowledge. Despite the many advantages of low-code, the existing literature reveals certain limitations. Therefore, we explored the key decision criteria that drive successful business application development when choosing between low-code or high-code solutions. Employing a design science research approach, we conducted three design cycles with 15 experts from both low-code and high-code domains. Additionally, a focus group discussion was conducted at the conclusion of each design cycle enabling the iterative refinement of our findings. Through this process, we identified 15 critical decision criteria. To ensure practical relevance, we tested these criteria in a real-world setting in an IT consulting firm by implementing them within a conversational agent.