Hiring practices particular to this field?

Is it normal that companies are not serious about hiring, take very long time and getting an offer is just not common

I’m not talking about job boards. Is it normal that you find a lot of positions that have not been posted yet, through perhaps word of mouth or recommendations, those companies constantly say you’re perfect for this, will send you an offer shortly, then just don’t?

I have not quite experienced this in other fields. Maybe it takes …

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