Salesforce Fact #893 | OLI insert/update triggers Opp triggers and flows
When an Opportunity Product record is created or during update if certain fields like Sales price/Quantity is updated, it executes the before and after update triggers and flows on related opportunity. So, we need to be careful while creating any automation on Opportunity Product. Reference: https://salesforce.stackexchange.com/questions/184659/opportunitylineitem-fires-opportunity-trigger