I'd think that if a therapist wants to be effective and do a good job, it could be very difficult and taxing. AND, if they're working with clients who have severe mental illness, it could be especially difficult.

But, I wonder if it's also possible for them to choose to put on cruise control sometimes. Maybe an easy client (like me) who doesn't make many demands (like me) who doesn't have serious issues (like me), then they can coast a bit.