The biggest part of an art collection is why people are interested in it. Most hobbies have similar effects where people are drawn and interested in doing something for psychological reasons.
For instance, if basketball is a prominent sport in a country, it's hard for someone to non conform with the idea of loving basketball because everybody loves to watch and play it.
Nevertheless, paintings of the past and present will project the memories of distant talents long gone. Still, the paintings are there to remind everyone that the human psyche and creativity make the world more enjoyable for everyone to experience.
The beauty of paintings is that you'll never know what you're getting when glancing at a portrait. Like what they always say: