Why Python is not both an interpreter and a compiler?

[Mahan Marwat]

> Python programs *could* easily be compiled the same way, but it generally  
> hasn't been considered all that useful.

If it hasn't been considered all that useful, then why the tools like cx_freeze, pytoexe are doing very hard!
And if it is really easy, then why cx_freeze, pytoexe developer are doing it in such a rubbish way instead of creating one (compiler)?