The source code for the poker software should be legibly written and it should be understandable for any programmer to read.  The poker company requires the poker software to be written legibly for many reasons.  As time progresses like any software, the poker software should also be improved to a higher version.  The upgrading of the poker software in most cases would be done by the programmer or the programming team that initially wrote the script for the software, but in some cases the company may prefer to have it done from somebody else.

When the company prefers to have the upgrading of the poker software done by some other software team, then it would be better if the script code written by the original programmer be written in a legible way with keynotes detailing the functioning of each code that is written.  If the script is going to come without any key explanations for the several codes, it will be difficult for the new team to decide on what variable has been assigned to what function and so on.  When the purpose of the script code is difficult to decipher or revealing about its functioning, then the new team will have to write new poker software than just upgrading it.

If the script code for the original poker software has been legibly written with key notes about the function, then the new team can just touch up the codes of those areas that need to be changed.  The work gets quicker and easily done.

The advanced versions of the poker software are not new software programs, but they are just modifications of the original versions that were previously used.  The changes in the latest versions are usually made to enhance the user friendliness of the software by making several advanced functioning corrections! It is for this reason that a latest version of poker software is preferred against the older ones. So, that is the story of the cosmetic surgeries done to poker software with every improving version.