Color choices

It's not unusual to find quite bold color schemes like this in old houses (often the typical post war standard houses), a striking contrast to the modern monochromatic nordic interiors. There must be an explanation to the from our point of view rather exotic choices of color but whether the reasons have been practical (usage of leftover paint) or artistic preferences I don't know, and I have never dared to ask the owners. It looks kind of sympathetic in my mind. Definitely not boring.