Hi, can someone could please explain how it works: BANNERS with ONLINE PLAYERS

I set up on site the banner that shows the players on the server and I noticed when I access the server thet GT delay of showing player and when players leave the server GT still shows 2-3min as the players still on the server.
Can thet banner be a little more precise or there is some refreshment program that looks at players on the server?

thanks

GT is not a live tracking service.