Missing chances in splinterlands

When I started to watch this battle I really thought that I will win, but than I was defeated by my missing monsters:

https://steemmonsters.com?p=battle&id=sm_HL1qKEMUq1J7nEXVAyqY&ref=mister.arianthus

So I really thought if this is normal and I played the battle again in slow mode.

My two attacking monsters tried to hit the Demonshark six-times when he had speed 5 and nine-times when he had speed 8.

So the theoretical chances would be:

6 x 20% (2 points Speed-diference) = 1,2 ... they missed two from 6 attacks.
9 x 50% (5 points speed difference) = 4,5 ... thes missed 7 from 9 attacks.

Just bad luck, they changed something or I oversee something ?