In Infinity, as in many similar games, a major part of play is stacking the odds in your favour. Keeping the opponent in your optimal range bands and keeping out of theirs, flanking and taking cover, and using equipment like mimetism or ODD while doing what you can to pierce the opponent’s tricks all serve to maximise your chances of rolling well.
But you still need to roll.
At optimal range and ignoring cover, I laid into an advancing triad with an HMG and rolled 18-19-20-20, and that about set the tone for the rest of the match. My people went down under the Tohaa’s withering glances, they could do basically nothing in return, and I was tabled halfway through Turn Two.
Such are games with dice!