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

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

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.

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Obsessing about clients outside of work hours.

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

Off the top of my ancient head:

Why cant I feel anything in my sleep? I cannot even feel myself moving, breathing, and swallowing saliva! I cannot even hear anything, not even my alarm! Some people that I've been with says that I'm moving a lot in my sleep, how can I stop it?

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

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

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

If sea levels were rising, wouldn't the acreage of coastal salt marshes increase? Are they?

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

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

Serious disappointment when the client cancels a session.

I’m a 25 year old teacher teaching at boys school & I have colleagues younger than me. I caught one of my students telling her he wanted her as his teacher instead & it hurt my feelings. They compliment her a lot. It makes me jealous. What do I do?

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.