"if abc was so good why would be people need to transfer it to standrd notation"

ABC is useful because you *can* generate the 5-line thing from it. Along with MIDI, various tab notations, and anything else the wit of humans can write programs to translate it into. And because it's ordinary text that can be posted around on the web, emailed, etc, and written in an ordinary text editor. And, likewise, use your ordinary text-search stuff to find tunes in amongst your collection of ABC tunes, if you have one, which is why it's useful to have one.

Because computers can be told what it means, basically.

It's not a competition.

I have heard of people who claim to be able to sight-read ABC, personally I can't. I write a tune as ABC because it's easy to generate standard notation from it, and I also get all the other advantages of having ABC on my hard disk (or webserver, or whatever) for other programs to do useful things with when I need them to.