What makes an artist like Leonardo Da-Vinci or Picasso more famous and considered greater than other artists? Why?

Limited output, compared to Demand. Influence, if relative. If buyers want crap, others will imitate.

Fame is in the buyers (and potential buyers) eyes. Advertising helps. If the Rich say it is what they want then instant fame.

Many People can take beauty for only so long. Then when something ugly comes along they have to adore it as a Change. You may note the same in Music, through the last century.

Picasso just happened at the right time. After a while the Elitists were stuck with it, and could not let go. So continuing Snobbery has caused it to rise in value.

All art has a value to each person in time. I like paintings that are photographic, but an occasional ugly or distorted work makes for a change and appreciation of the great works.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.