I have been using app for several years. I always placed waypoints Before intersections. I would add text so I could read and/or hear directions on screen: Exit onto Hwy 65. or Exit at # 134 (the green exit # on map).
Placing waypoint AFTER seems to be after the turn so you may miss it. Which and why it works best? I realize instructions are before you arrive at waypoint but I guess it is important not place waypoint after intersection very far.
@Roundabout Hi, for me there is a rule to place waypoints far awy from intersections and turns. You never know how many lanes are at the intersection and if the WP is placed correct on your lane and not on the other side.
The App will tell you early enough which exit and which direction you have to take.
My general "rule of thumb" is placing it several kilometer after a intersection.
first;
If you place it several kilometers behind the intersection you more likely to use the road you want to take and use less shaping point to create the route you want to make.
by placing infront of it, it might skip the road you want to take (depending on other point off course.)
Second;
there is a annoying bug (or feature) that may skip the spoken instruction if you place it in front of the intersection.
Sometimes I place a point in front of something special, but this are exceptions for me.
@Roundabout, it is best practice to place WPs on roads you want to ride, and not on crossings you want to ride. It is best to place WPs at least 250 mtr from any navigational directions. It is not needed to have "Exit onto Hwy 65" on a WP, since Navigation does that al by itself if you place WPs correctly 
@Roundabout
Your navigation system will tell you were to take turns. This is independant from MRA. No matter where to place a waypoint, your navigation system will tell you were to go on time.
I made it custom for myself to place waypoints after any turn. At long stretchy roads with intersections were i do not turn left or right i might just place one waypoint in the center.
Never had issues with taking wrong turns or whatever, my Garmin Zumo XT device always told me on time were to take turns.
@Ralph-Janssen said in Why put waypoints after intersection:
there is a annoying bug (or feature) that may skip the spoken instruction if you place it in front of the intersection.
This is the main reason if you use audio for directions. 
It's not a bug as such, the turn instruction and the waypoint are both going to get announced, and you really don't want to miss where to go at the turn, right?
Just position the waypoint a few seconds ride/drive beyond the turn and then you'll hear both announcements.
@richtea999
Never give it a thought why it doesn’t work when you place it before an intersection.
It makes sense that when there are two spoken instructions at the same time, they conflict with each other, and you don’t hear everything.
But in the end, I try to place my points on the roads I want to drive and make sure to place them after an intersection.
This can be challenging in the Netherlands because we have many small roads and intersections.
I only put waypoints or shaping points on a map for one of two reasons:
In the first instance the waypoint location is fixed by whatever it is that I am identifying. Before or after the junction is not my choice.
In the secomd instance it has to be after the junction or I risk the navigation device deciding on a different route to the one I want.
As I see it, the navigation device/app will give me navigation instructions. That's not the job of route planning.
I have been using app for several years. I always placed waypoints Before intersections. I would add text so I could read and/or hear directions on screen: Exit onto Hwy 65. or Exit at # 134 (the green exit # on map).
Placing waypoint AFTER seems to be after the turn so you may miss it. Which and why it works best? I realize instructions are before you arrive at waypoint but I guess it is important not place waypoint after intersection very far.
