What are some signs that a therapist may have poor boundaries with their clients?

Serious disappointment when the client cancels a session.

General Introduction to Boundaries from Panahi Counseling:

Struggling with fantasies of deeper connections with clients, whether sexual or parental or other intense or intimate relationships beyond psychotherapy.

What caused North Korea to go poor when at first it was rich?

Eager anticipation (or anxious anticipation) of the next session in ways that distract.

Frequent phoning or texting of clients to “check up on them and make sure they’re OK.”

Failing to mention the client in supervision/consultation, out of fear the supervisor/consultant will advise return to ordinary healthy boundaries.

If we colonized Mars, what would a human being from Mars be called? I’d assume Martian just as one from Earth is called an Earthling or Terran in the case of Sci-Fi media.

Routinely going over the time limit with certain patients, compromising the time for the next client.

Session-expressed curiosities about client details not relevant to the therapy.

Obsessing about clients outside of work hours.

Artists get better with age, e.g., painting. Yet when it comes to pop music, the famous work tends to be written when musicians are in their twenties. So, why aren't Bob Dylan or the Stones banging out amazing tunes now?

Sense of competition with persons who are important in the client’s life.

Disclosing feelings, fantasies, and experiences to the client in ways not related to the work the client is engaged in.

Off the top of my ancient head:

Investigative Reporters Sound the Alarm at Peabody Awards - Variety

These items can happen fleetingly, briefly, in any therapy, but if they’re frequent, it’s definitely time for the therapist to get some good, solid supervision/consultation.