Loser pays a proportion of the winner's costs equal to the loser's costs (i.e. loser spends £100 in legal fees, winner spends £1500 in legal fees, loser has to pay £100 of the winner's costs, leaving the winner with £1400 to pay) has some nice properties.
Even better - loser pays the winner the exact amount they paid their legal team. By their own admission "at arm's length" so to speak, that was the value of the litigation to them.
Um, wouldn't that enable people to ruin people's lives at will? Just sue them over and over. Even if the claims have no merits, eventually they will be bankrupt.
My understanding is that (in the U.S.,) the defendant generally doesn't recover any expenses. But I'm not a lawyer and all that. I guess they can counter sue, and courts generally don't tolerate people filing tons of frivolous lawsuits.