[nradov]

It's not really open ended. The client can stop any time they decide the legal fees are no longer worth the benefits. And even traditional law firms do often work on a fixed fee or contingency fee basis for certain types of cases.

[sjy]

You cannot stop any time you like once you start litigating. Capitulation, or paying new lawyers to get up to speed and continue fighting for you, will both result in very large immediate costs. In that situation many people will feel compelled to continue paying their lawyers long after the budget that supported the initial decision to litigate has been spent.

[nradov]

That's not how it actually works in expensive litigation. The type of litigants who can afford such legal fees at all do understand the sunk cost fallacy and are capable of making fairly objective decisions about whether to continue.