So our app uses some service to validate users & the validation response is received either by a callback url or by polling. Since their documentation states callbacks are rather unstable and "should not be completely relied upon", we only use polling. Client, however, wants to use the callback url and use polling only "after we are sure that callback has not been received". WTF. When we asked how will we know callback has not been received because it has not been received, we were told to start polling after like 1 hour.
?!?!?!?!?!?!