When a snowball is thrown at a mob, the projectile will occasionally pass directly through them without colliding. Only confirmed to happen in survival and adventure mode against non-player entities. Not confirmed to happen with players nor with other projectiles.

Steps to reproduce:

1. Create a fresh world (superflat would make testing easier)
2. Give yourself a large amount of snowballs (i.e. /give @s snowball 320).
3. Go into adventure mode (i.e. /gamemode adventure).
4. Summon a husk (i.e. /summon husk).
5. Repeatedly throw snowballs at the centre of the husk's hitbox.
6. Although non-deterministic, eventually one of the snowballs should pass through the mob without colliding with it properly, and via repetition, this should be observable approximately 1 in every 50 or so shots.

To make detection easier, a repeating command block with the following command should make it easier to observe the projectile's path:

/execute at @e[type=snowball] run particle end_rod ~ ~ ~ 0 0 0 0 1 force