What are your biggest hiring RED FLAGS?

Lack of accountability (goes hand in hand with bad mouthing previous employers), being unable to find the line between becoming unprofessional and giving a glimpse of personality, lack of interest in learning (related to entitlement).

If they aren't able to explain complex concepts boiled down to it's basics. Also, bad mouthing previous employers or co-workers.

As a recruiter, one of the many red flags for me is when they underestimate me with sentences like, "I cannot answer that question because you wouldn't understand since you are not a tech." Imagine matching that profile with a junior who needs coaching to learn new things? Imagine that profile in a meeting with a non-tech client! Red flag: when they think HR interviews are just a waste of time.

Tardiness (Specifically for remote interviews) and lack of engagement (being too cool to be excited).