Seldom, but some qs are so indistinct that more info is needed.
Learn to think about the q. Imagine somebody that knows nothing about the subject reading it. Avoid initials and abbreviations. Use standard English, not 'yoof speak'.
It is not here is a list of words that the rule q is followed by u does not apply to:
buqsha faqir QADI QIAD QANAT QASIDA QAT QAWWAL QAWWALI QIBLA QINDAR QINDARKA QINTAR QIGONG QIN QINTAR QIVIUT...
The reason we use "qu" relates to Latin, but also to the Norman French, who conquered England in 1066. In addition to ruling the land, they also changed the spelling of English to suit them better....