Why do ;ooks matter I a relationship but not race?

No , this is not an absolute fact , for some people race is important for others not , for some people looks is important for others not

Race does matter to some people. Things like age, height, income, religion, etc. matter to some people too. You don't get to tell others what they should or shouldn't prioritize in a partner. The trick is to find someone with the same priorities you have.

ATTRACTION matters. So many people are with someone they aren't even a little attracted toward, i've noticed. That would not work for me.

There are people that prefer to date certain races or not outside their own race. Some make it a strong preference some a mandatory thing.

After WW2, scientists discovered that humanity cannot be categorised into distinct "races". Everybody has thousands of genes, spread over 47 independently passed-on bundles of DNA

There's good looking people in all races which probably answers the question you ask, but with race often comes prejudices that family members may make things quite difficult for a relationship to succeed without interferences.

Because regardless of race depending on your preferences you can find example some germans really attractive but not all and you can find most african Americans unattractive but not all. Also depending how old school an immigrant house hold is race is important example my friends brother was half czech half polish. His girlfirend was full polish. Her family chased him off because he wasnt full polish. My situation is a little more relaxed. Im half irish half english my current partner is a quarter, not half, not full, quarter. This is acceptable short term but not long term. Having children will mean they would be 2nd generation bitsers and that cant be done. any involvement with children means they have to remain half or 3/4. I may possible get away with quarter children but dont know. My cousin got away with children that are 1/4 irish 1/4 welsh and 1/2 english so not quiet quarter but yeah.