It is only wise to consider people have similar characteristics to become friends than opposite has the connection between the two of you will make the friendship last long. Opposite characteristics will only soell doom for the friendship has there will be lack of understanding which isn't good in the friendship. We need someone who can have our back and assist in time of our need. Good friends are loyal and accept you for who you are during the good and bad times. Love the illustration of using the case of nationality in another country, that gives a good picture of why similarities should placed has utmost priority.
However sometimes two different kind of people can work together and become good friends it depends on the Quality of loyalty and trustworthiness is found. People with similar qualities tend to break one heart or stab one at the back. At the end it is all watching carefully and been very selective and watchful of who we chose has our friends. Sometimes opposite usually attract has it makes it more fun. As long as there are loyalty, trust and respect between both friends, the relationship will stand the test of time.