ERR_CPU_TIME_LIMIT on Salesforce: Apex CPU time limit exceeded. Root cause: Salesforce Apex code exceeded CPU time limit (10,000 milliseconds for synchronous, 60,000 for asynchronous). Common causes: inefficient SOQL queries in loop, large data processing without batching, recursive function calls, missing indexes on queried fields, complex business logic in trigger. Step 1: Kill Nested Loops. Never place a SOQL query or a secondary data loop inside an existing collection loop (O(n²) complexity). Step 2: Utilize Developer Maps. Query your collection database targets once, store the output values inside an Apex Map<Id, SObject> collection layout, and fetch key matches instantly (O(1) complexity). Step 3: Consolidate Automation Rules. Profile your object automation rules. Combine multiple overlapping Process Builders or record-triggered flows into a single unified Flow per object.