• Unique entry per Cohort : Each user can enter a specific cohort only once. For example, if User A performs the initial action on July 1st twice on the same day, they are counted only once in the July 1st cohort.
• Multiple Cohorts Entry : A user can enter multiple cohorts. If a user A comes back on a different date and performs the initial action on another date that constitutes a  different cohort,  the user will also be included in that specific cohort’s count. 
• Unique entry per return interval : A user can only be counted once per return interval. For example, if you define the return interval as a week, User A will only be counted once in week 0, once in week 1 and once in week 2, etc. A user can be counted more than in the column, but only once per cell. 

When you select a start action and return action, you will be asked to to specify how many times this action should be done before starting the retention analysis. 

If you are selecting a single start action, then that action must be triggered as many times as you define your minimum count for the analysis to start. 

If you are selecting multiple start actions, the minimum count refers to the cumulative occurrences of any combination of the selected actions. For example, if two distinct actions are chosen, and the count is set as "at least 2 times," the results may include two occurrences of a single action or one occurrence of each individual action. This provides flexibility in how you define the start of the analysis based on user interactions.