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

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

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

Off the top of my ancient head:

My boyfriend always verbally abuse me and makes me cry. If I try to tell him how hurt I was, he says to me he loves me and can't hurt me but always abuse me. Why?

General Introduction to Boundaries from Panahi Counseling:

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

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

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Serious disappointment when the client cancels a session.

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

Obsessing about clients outside of work hours.

Have you ever had a scary dream about a loved one or friend soon after their death?

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.

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

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

How did Neo defeat the architect at the end of The Matrix: Reloaded? Was it solely due to his belief in himself or were there other factors at play?

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