Holding up till the end of the game can be very risky, it's better to cashout before the game is settled fully and you losing the bet. My goal is to make profit when I do parlays, combining more than 10 games on a bet slip should give you an awareness that Anyone of those games can ruin your entire bet so instead of letting that happen try not to get greedy and just take whatever amount the bookies offer.
Some times, it's greed that makes some people not to accept cash out, they could think they are being smart by holding unto the game until they lose everything when the game bust. I have learned so much harsh lessons from losses that I deviced a strategy of staking on parlays and ever since I started using the strategy, I don't give chance to winning opportunities. It's either I accept one cash out on the first slip and allow the second slip to play out.