On the XT and a few slightly earlier models:
Waypoints entered into Basecamp using the flag tool will ALL become favourites.
Any other point - usually dragged and dropped into place do not
normally become favourites. However, sometimes the point that you place may land on a location that is already saved in the Garmin database - in which case it will be a waypoint, and get saved in the XT as a favourite. Only waypoints will appear in the bottom left pane in Basecamp - along with the routes and tracks.
Once you have all of your points in your route, any of them can be made into either Via Points or Shaping Points. Via Points will alert as you approach and on arrival. They appear as an orange flag on the map and in the trip list. Shaping points do not alert. They are shown as small blue discs.
When you press 'Go' and you are then asked to 'Select the Next Destination', only the Via Points are given as choices. Not the Shaping Points. So that has nothing to do with the favourites or Waypoints.
When you select a Via as the next destination, the satnav treats that as a 'jumping in' point and navigates you directly to that point, disregarding any of the route that you have plotted up to that point. It then navigates the rest of the route from there.
Via Points are usually for key places that you know that you will pass through - eg coffee stops. so you may have 2 or 3 in your route. All of the rest are probably shaping points. Shaping points are a bit more forgiving if they are inaccurately placed - but I wont go into that now.
A good tip is to NEVER put your start point at the place you start the engine. Put it on the road that you want to be on once you get going - eg outside the town or a mile or two up the road. Select the start point as the next destination, and the satnav will get you there and then continue with your route.
One other comment - the XT will change the name of route points from what you entered in Basecamp - which is a bit annoying. But it never changes the name of points that were created as Waypoints with BC flag tool - ie the ones that end up in Favourites. Garmin are aware of this problem, and say that they are working on it.
All of this and more, nicely illustrated, can be found here:
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