Plan gaming sessions for enjoyment.
A session plan fails when queue time is ignored: a twenty-two minute match with a four-minute queue occupies twenty-six minutes, so an evening fits five rather than six. Subtracting scheduled breaks first, then dividing the remaining time by the full per-match cost and flooring the result, gives a match count you can actually finish — important when abandoning a ranked match halfway carries a penalty.
Usable play time
Play minutes = available minutes - 5 minutes per scheduled break
Matches that fit
Matches = floor(play minutes / (match length + queue time))
Because starting a match you cannot finish is worse than not starting it — competitive modes penalise early leaving, and unsaved progress in a level is simply lost.
Eye strain and wrist discomfort build with continuous play, and a short break each hour is the standard mitigation. It also happens to be when reaction times start to drift.