People who save others first vs People who save themselves first

Why do some people risk their own lives to save others? I think that some people save others first becaause that person may have a kind and caring heart when it comes down to saving others. They may not want to see others get injured infront of them. The person who tries saving others from danger may be a cruel looking person. If the person in danger gives this cruel looking person a chance to save them they may never judge again. This cruel looking person may have endured horrible life making their hearts cold and feelings heartless. It may take one trajic event to occur to make everybody come together as one.
Some people may look out for themselves first before anyone else because maybe they need to know what circumstances they are in before they go trying to save the whole world. I personally think that I would look out for myself first so I can know what precautions to take into action before i go saving everybody else.