Placebos can be effective especially to find out if a treatment actually is effective or not, or if the idea of the treatment is just as effective as the actual treatment. There are plenty of documented examples of when people simply believing they were receiving treatment showed substantial improvement in their condition, proving psychosomatics can have a lasting impact. But overall, without using placebos, we wouldn’t really be able to gauge the effectiveness of an experimental treatment or medication, and we wouldn’t have a way to find out which side effects are caused by psychosomatics and which are caused by the treatment itself.