I doubt its about screwing over opposing counsel(altho like any other ego-driven effort or personality type im sure it also happens), more like better lawyering to get an outcome they can brag about to future clients. Im sure some or many want to not only do justice to the cases they accept but also give their clients some sense of closure, whatever the outcome

The worst thing is often the uncertainty and the way it makes it impossible to plan your moves going forward. Even if you lose, its better to have closure on that so you are able to make the best moves to recover and chart a better course now that the fallout is established

Especially if a victory can be known or projected to be “pyrrhic” and open the door to a harsher big picture outcome for their client. Lawyers are known chess appreciators for a reason, im sure many arent totally cool with bilking a client to fund their own foreseeable destruction but again, it almost definitely happens