On the topic of art - why o why do I see so many art galleries / museum not not lit up properly? what would be the reason I wonder.
The reason is most art objects are light-sensitive, and museums have dual aim - to show their collections in best possibly light and to prevent damage, caused by light.
Museum lighting and illuminating works of art is a science, there is a lot of scientific research on this subject. There are lab techniques developed like Microfadeometry to measure the detrimental effect of light. The aestetic impact of light is another concern. Any good museum invests a lot of effort in good lighting and is lit properly, but "properly" simply does not mean photography friendly.
