When betting parlays, one of the key risks to consider is the increased likelihood of losing the entire wager due to the requirement that all selections must win for a payout to be received. This makes parlays significantly riskier than single-game bets, as even one incorrect pick can result in a total loss. Additionally, as the number of legs in a parlay increases, the odds of winning decrease exponentially, leading to a false sense of security if bettors are overly confident in their selections.