How many reviews should I expect during the device design ?

Quality systems standards do not specify how many reviews I should expect during the device design prior to its conclusion, that is when placing the product on the market. The number depends on the complexity of the product. However, the following points may be assumed:
• design startup;
• feasibility analysis results;
• authorization to realize the first functional prototypes;
• authorization to realize the advanced prototypes;
• output data confirmation/authorization to realize pre-series;
• clinical validation results/certification tests results;
• marketing authorization.