💬 In plain words: Before-save updates in Salesforce are entirely free from a performance standpoint. Because the record is already open in memory, you are simply writing on it before it gets saved. After-save updates, however, force the system to re-open the record and run the entire save process all over again, essentially doubling your resource cost. The golden rule is simple: if you are changing the exact same record that triggered the flow, do it before the save. If you are updating related records, do it after the save. The Core Concept: Memory vs. Database A before-save flow modifies a record while it is still in the system's memory, right before it is permanently written to the database. No extra operations: It doesn't require an additional DML (Data Manipulation Language) statement, meaning no second save cycle. Lightning fast: Because triggers don't re-fire, Salesforce states that before-save updates are roughl...
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