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.

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

General Introduction to Boundaries from Panahi Counseling:

Why do some people hesitate to say 'I love you' even after their partners have said it first? How can one interpret this behavior from their loved ones?

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.

Serious disappointment when the client cancels a session.

How did the DMK alliance manage to keep the BJP out of Tamil Nadu politics all these years? Is the picture now changing in Tamil Nadu after the entry of Annamalai?

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

Obsessing about clients outside of work hours.

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.

Why do narcissists avoid talking about the real issues?

Off the top of my ancient head:

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

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

Why didn't my ex fight for our relationship? He gave up so easily.

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