In many countries you cannot plea out. Everything has to reach court, and I as living in one of these countries think is a good think. This prevents extortion and bullying by prosecutors. Your sentence should not depend on your skills at negotiation and knowledge of judicial processes.
I know for sure Sweden but I think most civil law countries lack the concept of a plea bargain, which means most of world. For example France introduced limited plea bargains first in 2004.
Edit: Seems a bunch of civil law countries have introduce plea bargains the last 15 years, but before that almost none of them had it. This makes it a bit hard to find a concrete list of examples since almost all hits are about the countries introducing it with little discussion about why some countries do not do the same.
