The phrase "clear stages" can be replaced with a variety of words to convey similar meanings. For instance, the word "distinct" can be used to emphasize the individuality or separation of the stages. The phrase "well-defined" can be used to suggest a clear and precise understanding of each stage. Similarly, the word "crystal-clear" can be used to convey a sense of transparency and clarity. The phrase "unmistakable" also suggests a clear and easily recognizable progression. Another option is "evident," indicating that each stage is easily observable and apparent. Finally, "unambiguous" can be used to suggest that each stage is clearly defined and not subject to interpretation.