Sometimes you just have streaks of bad luck. In my main game with a massively OP character, I failed 14 attempts to install an internal furnace at 14% - but I succeeded on 80% failure rate ones numerous times. I had most of the late-game bionics installed and still failed every single internal furnace.
Sometimes that low chance just happens numerous times in a row.
I would recommend trying a debug character and spawn in a few dozen to make sure it isn’t a bug though.
