When you’re out and about and unexpectedly hear someone call out your name, never turn to look the first time. Wait for the second or (preferably) third time they call.
If you need reasons, here are some:
(1) You may have mistaken what you heard.
(2) They may be calling someone else, and it would be awkward if you were the one to respond.
(3) Now being more alert, you will have a much better sense of the caller’s direction.
(4) You will give yourself more time to decide whether you want to pay attention to this person in the first place.
Ivan Cortes 