when a projectile is thrown or shot from a bow, it doesn't face the direction that it is actually going in.

Projectiles flying east or west will face the opposite way.

This gets particularly annoying as projectiles flying diagonally, that is, moving both in the x and z axis, will look 90 degrees to the right of their movement direction. If they're only slightly going diagonally, it's something inbetween this and the state described above.

On the image I have suspended 3 snowballs in the air with a teleporting command block and enabled hitbox vision to show their looking directions. The actual directions they're going are marked with red arrows.