We need to distinguish between civil and criminal courts. While both have similar rates of "settlements" the reasons why they are struck are very different.
Edit: What I forgot to mention but is super important, the vast majority of lawsuits are super boring. Even in criminal court, for every rape you have 35 people committing larceny theft. You don't need to go to trial for every single minor theft. So that 5% that go to trial would be the 1 rape and one theft. Same in civil court, most are such petty boring disputes that shouldn't even be brought up to the court.

In criminal court, the main reason is, things only go to trial if there is sufficient evidence. Otherwise, the prosecutor would drop the case. So the defendant knows they are guilty, they know the prosecutor has a decent amount of evidence, and going to trial has little benefit. By pleading guilty they get a reduced sentence but are still found guilty. Only pleading a "no-contest" would mean they aren't found guilty. But the court usually has a say in whether that's an option or not. So everyone involved saves time and the "criminal" gets their fair verdict anyhow. It's not like they go free just because of a plea bargain, well in most cases at least.
If we go further and look for example at Japan, the conviction rate there is at 99%. And that's because prosecutors drop almost half of the cases. If US prosecutors would work under the same guidelines as Japanese prosecutors, the conviction rate in the USA would also be above 99%. By extension that also means lawyers have a really good understanding of whether or not a case has a chance during the trial. If there is no point and everyone involved just knows how this is going to end, involving a long trial is not beneficial for anyone. A judge is still involved in the verdict and is saying this is fine.

Of course, there is the issue of innocent people taking a plea bargain. Something that shouldn't be happening but is an unfortunate reality that doesn't relate to your question.

In civil court, the disgusting and immoral part is that so many lawsuits have to be filed in the first place. Civil court is mostly about making one party whole. Which in an ideal scenario is happening without the involvement of the court at all. But getting a verdict or judgment wouldn't do anything. It is still just making one party whole. It just takes longer. And since a lot of cases are grey areas where both parties have reasonable arguments in their favor, finding a compromise is perfectly reasonable. A lot of time there isn't 1 side with 100% at fault.
The USA is a little bit unique in that regard since it's one of the few countries that award punitive damages. And whether or not punitive damages are a good thing is a whole different discussion. Most other countries only allow reimbursement for lawyer costs in addition to the actual damages. Funnily enough, in the USA that's less common.