Miss chance? RNG

Tiltowait

Different targets, same attacker. 100 misses in a row. Attacker is 4 star level 53 gear 5. Targets are level 42-45, 3-5 star.

Actually tried retreating and starting over, then out of curiousity did that over and over just to see. Have not hit yet. So...basically auto misses are hard coded into the system? And target properties are irrelevant?

LastJedi

If you retreat and redo GW with exact same squad/lineup, the result is repeated. It is stored in memory.

Timitock

Swap the places of two on your team and try again.