Hi this is a bug that has been tormenting me since 2017 but as a young lad I didn't know these forums existed.
When you make a line with a stroke add round caps to that line. Add a trim paths & enable motion blur.
Than animate the start from 0 to 100%.
You get a nasty ghosting artifact when the line should completely dissapear.
You don't have this issue with the butt cap.
Here is a gif of the issue. I also dropped a download link below.
With the project file.
Hopefully you guys & gals can look into this 🙂
M1 Max, Ae 23.0.0