POI alert distance not radius?

Are all GPS units the same?
As in, when I come close to a POI that I have an alert set for. Say at 1000FT the alert isn’t going off until I am on the road the POI is on and heading toward it.

If you select go to depending on how you set the alert you can be alerted and not be on the same road.For example when I travel down I95 and I75.I have my Cracker Barrels set for 8000 ft.I have gotten alerts while on the interstate.Same example not selecting go to but with the proximity alert at 8000 ft I can pass right by the same one from the interstate that I was alerted for before and not get the alert .

Some users for certain custom pois like to be alerted when not on the same road like the interstates.They take the custom poi file and add TourGuide to the name and set the alert for example two miles using poiloader.Using TourGuide in the file name will give you a radius alert instead of along the road based on the coordinates.You can find info on this on poiloader help and many threads here on the subject.

Are all GPS units the same?
As in, when I come close to a POI that I have an alert set for. Say at 1000FT the alert isn’t going off until I am on the road the POI is on and heading toward it.

I have one POI I drove up on a side road behind it and the alert didn’t go off even though I was like 50 FT from the POI

I have the Garmin 855

So I think I am asking are all GPS units NOT set to a radius in distance but only by route point A to Point B distance? (Point A being where you are on the road when the alert distance has been met and Point B being the POI)