should have rung

[keannu]

Anyway, the result is that despite the judges' prejudice for male players' role for a specific musical instrument, she passed the audition and made it big. So considering the result, does this "should" mean presumption of past regret? Is "ring an alarm bell" an idiomatic expression?

ex)At the beginning of her career as a professional musician, Abbie Conant was in Italy playing trombone for the Royal Opera of Turin. In 1980, she applied for various orchestra jobs throughout Europe. She got one response: the Munich Philharmonic Orchestra. "Dear Herr (Mr.) Abbie Conant," the letter began. Looking back, that mistake should have rung alarm bells in Conant's mind.

[5jj]

Neither.

Stop trying to label things, keannu, and just work out what they mean.

[keannu]

Neither.

Stop trying to label things, keannu, and just work out what they mean.

I can't understand what it means, maybe it is "a guess", anyway I need some categorization or label, what it is called. Okay apart from labelling, does it mean "it could have rung alarm bells"?

[5jj]

I can't understand what it means, maybe it is "a guess", anyway I need some categorization or label, what it is called. Okay apart from labelling, does it mean "it could have rung alarm bells"?

No. 'should' does not normally mean 'could.

It means something like At the time it would have been reasonable/appropriate to expect that she would feel some sort of warning signal.