why is new birth so necessary?

From Tim Challies' blog as he's blogging the reFocus Conference:

[John] Piper offered ten biblical descriptions of man apart from the new birth, ten reasons we need to be born again. As bad as the news is, it’s glorious to get it right because there is a glorious remedy. When we properly understand our own badness, we see Christ more gloriously.

Apart from the new birth we are dead
Apart from the new birth we are by nature children of wrath
Apart from the new birth we love darkness and hate light
Apart from the new birth we have hearts that are hard like stone
Apart from the new birth we are unable to submit to God
Apart from the new birth we are unable to except the gospel
Apart from the new birth we are unable to come to Christ or embrace him as Lord
Apart from the new birth we are slaves to sin
Apart from the new birth we are slaves of Satan
Apart from the new birth no good thing dwells in me