Hi @Ssaini1 ,
Here is the explanation:
onStart: executes at the start of an import before any rows are read
onAfter: executes at the end of a row transformation and after the source row has been transformed into the target row and saved
onBefore: executes at the start of a row transformation and before the row is transformed into the target row
onChoiceCreate: executes at the start of a choice value creation before the new choice value is created
onComplete: executes at the end of an import after all rows are read and transformed
onForeignInsert: executes at the start of the creation of a related, referenced record before the record is created
onReject: executes during foreign record or choice creation if the foreign record or choice is rejected; The entire transformation row is not saved
