For much of the year the outdoors only becomes usable once the sun has gone, which is why running tracks and parks fill up at hours that would look strange elsewhere. If 8:05 pm is when you mean to be out, the countdown here gives the exact wait rather than a rough sense of soon.
This is a display rather than an alarm. Nothing rings, buzzes or notifies at the end, and the page will not interrupt whatever else you are doing. If being interrupted is the point, set an alarm as well and treat this page as the running total you can glance at in the meantime.
Twelve o'clock is where the 12-hour clock is weakest: 12 am and 12 pm are read the wrong way round often enough to cause real trouble with bookings and deadlines. Writing the same moment as 20:05 removes the problem entirely, because a 24-hour figure only ever points at one instant in the day.
Common questions
What is 20:05 on a 12-hour clock?
The same instant is 8:05 pm in writing and five past eight in the evening out loud. Anything from 13:00 onwards loses twelve to give the pm figure, which is the only sum involved in moving between the two.
Does the number update by itself?
Yes. It is recalculated every second from your device's clock, so nothing needs refreshing or restarting. Whatever is on screen is the current gap to 8:05 pm, not a figure worked out when the page first opened.
What happens once 8:05 pm has passed for today?
The count rolls over and carries on towards the same time tomorrow. That happens on its own at the moment the time passes — the page does not need reloading and there is nothing to reset by hand.
Which clock does the countdown use?
Your own. It reads the local time and time zone from the device in front of you, which in the Emirates means Gulf Standard Time, UTC+4. Travel and the count follows whatever the device picks up.