Why some languages are written right to left

http://www.chabad.org/library/article_cdo/aid/2920308/jewish/Why-Do-We-Write-Hebrew-from-Right-to-Left.htm

According to this article it seems all languages were writtenright to left when they were chiselled into stone but after ink was invented then it was better to write left to right to avoid blots.Hebrew already being written so much in stone remained right to left.

As to why some people are left handed,I am ignorant.But it’s awkward for them learning to write with pens