Highs whiff on crouching opponents if they are not blocking.
This includes:
- Grabs
- Projectiles
- Normal Attacks
The same highs will make contact if the opponent is crouch
blocking.
Some highs have very strange hitboxes and will still whiff on crouch
blocking opponents though. Against taller opponents the same move will still be blocked if they are crouch blocking.
This includes:
- Frosts projectile
- Johnny's fireball vs some characters
- Kano's standing 1 and the second hit of his F12
You could also get low poked out of a high even if you are at advantage.
Highs are generally safer moves, fast moves, end in strings that are + on block, or have mixups built into them.
This means that you have to condition your opponent to block so the first hit makes contact with their guard OR properly space and time the attack so it makes contact in footsies/neutral.
If your opponent does start disrespecting the high and starts low poking out every time you try to go for one, mix in some fast mids or lows to discourage them from pressing buttons while they are at the disadvantage.
Hope this helps.