Why doesn't Latin, and its Romance daughters, use the letter 'k' much?

Factual Questions
1

While ‘K’ is part of the Roman Alphabet - and taken straight from the Greek I assume, why is it basically unused in Latin? Now I know at one point the ‘C’ was always hard, but at some point it softened before e, i, or y and to permit a ‘k’ sound before those vowels, the qu or (in Italian)ch was used. but why didn’t the late Romans/early Romance writers use a ‘k’.

Even now when ‘k’ is used in French, Spanish, Italian, or Portuguese; it is mainly for words of foreign origin (kiosk, kilometre/o)…and even there thwere is a tendancy to ‘Latinise’ the word by ridding the k. (quiosco, quilometro).

Why this aversion to the ‘k’?

2

Very observant. The Greek Kappa came from the Semitic Kap. The Semitic sound value for the letter K was maintained in Classic and Modern languages, but Latin itself abandoned K almost entirely for C. Because the C was hard in classic Latin, the letter K was used for primarily for words borrowed from the Greek. I suppose as time progressed and the connection to the Greek language became more tenuous this happened less and less often, and C became the dominant letter for the /k/ sound. So the Romance languages only use K for foreign words.