"Not always - we've argued before about a 'very professional' performer who occasionally vomited over the audience - he had an alcohol problem and unfortunately many audiences encouraged his behaviour and it became part of his act."
a generalisation from one particular case, something that you do on occasions.
the vast majority of professionals are just that, professional , they turn up on time, they are well practised, they are skilled and their performance is of a high standard.
I know of only two cases of performers vomiting on audiences one was an IRISH FEMALE TRADiTIONAL SINGER AND THE OTHER WAS THE PERSON YOU ARE REFERRING TO.
2 occasions in 40 years.