When you have a legal issue, there are typically two aspects of your case. There are the "merits" of your claim. This is what most people understand to be your legal issue. The merits of a case are important; if you have some problem that is not really suited for the courts, you may be frustrated by the process and unsatisfied by the results.
During litigation, you presume the other side is going to fight as aggressively as you are to win. However, on occasion, you may come across another party who folds almost immediately or shortly after the litigation begins. This can be optimal, although how optimal may depend on the reason behind the default.