Ordering an extra test or an extra drug is mostly a doctor covering themselves from potential lawsuit.
People are tremendously impacted, for good or ill, when prescribed pain medications, ADHD medications, anti-depressants, etc. Many of these people are harmed. Many of the doctors who caused them harm simply do not care.
Then before you know it, you have to take a pill to take a pill. Then down the road, you have to take a pill to take a pill to take a pill.
I'm no medical Calvinist either, but I am not sure that polypharmacy should be the end goal if it can be avoided.
Doctors may care about treating patients, but hospitals only care about one thing -- money. Pressuring doctors into pursuing unnecessary treatments are one of many ways hospitals try to increase revenue.