If police notice a statistical pattern in the race that commit crimes, is it then racist if they follow that pattern when doing random searches?

If you have 500 bad experiences with 500 different staff on different occasions with a large company, is it prejudice if u stop communicating with that company?

Let's say you have 20,000 experiences over a set period of time. 500 of them are bad experiences. What if all the good experiences are from various countries, but all the bad experiences are with people from a specific country, is it racism if u decide to stop communicating with people from that country?