Urgency is the oldest trick on a sales page, and you can test it in about a minute. Open the page in a private window, note the countdown, then reopen it a few minutes later. If the timer starts over, it was never counting toward a real deadline.

Do the same with stock counters. A message like 'only 3 left' on a digital product makes no sense, because a download file cannot run out. For physical goods, check whether the number changes when you reload.

Finally, look at the bonus that 'expires tonight'. If the same bonus is offered again on the order form tomorrow, you lost nothing by waiting. Real deadlines have a date, a time zone and a reason.

Full guide with examples: https://worthorpass.com/blog/countdown-timers-and-scarcity/ (Worthorpass earns affiliate commissions on some links; it does not change our scores.)