Addiction: Because the spread from dysfunction to function is so vast especially with buprenorphine and MAT.
Neurostimulation: Because with ECT, similar concept, people go from years of depression, even on disability, to now being able to function. One patient was like, 'shoot, I'm 50's and now I feel well and can actually work, what the heck do I do now that I'm not just sitting on couch at home?' Or family members who are delighted to get grandpa back from the severe depression/psychosis.
Least: C&L, because its essentially a service that exists because of bureacracy, i.e. patient needs inpatient psych, just had SA, and primary service doesn't want to arrange the transfer or write the state required hold documents. IMO, all of C/L can be done either by the primary service or a SW. Most of the time its just an antipsychotic writing service (despite more literature coming out saying they don't anything for behavioral disturbances or delirium and probably better off not using them). Or you start zoloft 25/50mg. Most of the time the primary service doesn't read the notes. Or its a rubber stamp template for delirum; reduce opioids, avoid anticholinergics, don't use benzos (some data debates that one), don't use antihistamines, find the under lying etiology, reduce polypharmacy, etc. Conversion disorders are essentially consults because neurology doesn't know how to talk to their patients and point them towards a therapist... Crying/sad, surgeons don't want to spend 5 extra minutes of empathy. Capacity consults, primary service is capable of doing, doesn't require a psychiatrist to do it. C/L is a complete waste of psychiatrist's time. All the complex cases or medical zebras, don't require psychiatry, and psychiatry is merely a passive observer to the services that actually treat or manage it. The only condition I could think of that really could be a possible C/L case that warrants such a service is NMS or malignant catatonia requiring bedside ECT in ICU. Transplant C/L is worthy of their title, but that's a different beast. /rant