Perhaps it's because in all but the simplest cases, you need 2 or more concatenations to achieve the same result as one single f-string? "literal1 " + str(ex

Perhaps it's because in all but the simplest cases, you need 2 or more concatenations to achieve the same result as one single f-string? "literal1 " + str(expression) + " literal2" vs f"literal1 {expression} literal2" The only case that would be faster is something like: "foo" + str(expression)