Wikitude

I have a simple code change in POI Examples from Github. I have made simple change in the code 

    locationChanged: function locationChangedFn(lat, lon, alt, acc) {
    

           World.locationUpdateCounter = World.locationUpdateCounter + 1;

        document.getElementById("locationUpdateCounter").innerHTML =  
         World.locationUpdateCounter;

...

 Initial value for   World.locationUpdateCounter is 0. 

On the screen number go  to several numbers up and then starts again from 0 . 

How can this happen? World is reinited multiple times per minute?