word wrap和word break为啥设计成一个属性?

 word-wrap:
The word-wrap property is used to specify whether or not the browser may break lines within words in order to prevent overflow when an otherwise unbreakable string is too long to fit in its containing box.
 word-break:
The word-break CSS property is used to specify whether to break lines within words.

上面是官方的定义
在实际使用上,我发现,这两个属性可以单独使用
word-wrap,可以切换两种状态,"不截断单词","另起一行后再截断单词"
word-break,可以切换两种状态,"不截断单词","不另起一行并截断单词"
如果两个混合用,好像是word-break更具优先权
这两个属性,完全可以合并的,用三个取值可以表示三种状态
为啥要分成两个呢